Older cat not accepting raw?

Recently I decided to make the transition from wet canned food to raw for my 3 cats. I read that you should do it slowly to avoid digestion issues.
My two youngest (they are both almost 2 years old now) love the raw food! I've just been giving them some roughly chopped chicken breast and a few chicken hearts for one meal and then their usual pouch of wet food for their second meal. When I cut out the commercial food, I will also add bones and vitamins to the raw. Basically I'm in the experimentation stage and it looks like it will end very well for my youngest cats.
My oldest cat (14.5 years) on the other hand wants nothing to do with the raw food. He will hardly sniff at it, never mind eat it. I'd really like to get him switched because according to his blood test results he does have slight kidney issues, which will probably progress to renal failure. He has always eaten dry kibble, up until about 6 months ago when I slowly got him on wet food for the added moisture. He has always had digestion issues since he was a kitten. I'm thinking irritable bowel syndrome or a possible allergy to the wheat in the cat food itself.
He has no objections to eating cooked chicken. He loves it very much. My question is should I just feed him my own homemade cooked cat food since he is older and I don't want to stress him out by forcing him to eat raw? I'm thinking that a cooked homemade diet is still going to be healthier than any commercial cat food.

What would you do?
Thanks!

For the younger 2, are you wanting to feed ground or frankenprey?  Which recipe are you following?  I'm assuming that you've only been feeding raw a very short time, and if 50% of their diet is raw then we need to make sure that it is balanced. 

You can absolutely feed a cooked diet and add a premix or vitamin/mineral supplement and eggshell powder for calcium for the older kitty.  Bone has a lot of phosphorus in it and it's generally advisable to reduce phosphorus in kitties with kidney disease.  It might be helpful to know his kidney values so that more experienced members can help you with diet.

Thanks for answering!
Yes, I am very new to this whole raw feeding thing. In fact, I've only been experimenting with it which is why it isn't balanced yet. I wanted to see if my cats would even eat raw meat before jumping in and buying all the ingredients. I was thinking about following this recipe: http://www.catnutrition.org/recipes.html

2 kg [4.4 pounds] raw muscle meat with bones

400 grams [14 oz] raw heart
200 grams [7 oz] raw liver
16 oz [2 cups] water
4 raw egg yolks
4 capsules raw glandular supplement
4000 mg salmon oil
800 IU Vitamin E
200 mg Vitamin B-50 Complex
1.5 tsp. Lite salt (with iodine)
4 tsp. psyllium husk powder

I hope that this recipe sounds okay! I found a local site that delivers frozen meat for pet food and they make their own grinded poultry (including the carcass). I was going to go with that for the 2 kg. of meat and occasionally throw them some chicken necks to chew on. I want to transition them to 100% raw.
As far as my oldest cat goes, honestly I don't know his kidney values. He was having slight blood in his stool, which is why the vet decided to check his blood. All she told me was that his kidney levels were a bit off, nothing too alarming for an older cat, and then handed me a sack of very expensive Hill's Science Diet Renal food. I thought that there must be a better way than treating him with more dry food, which may have caused the problem to begin with!
I was going to follow this recipe for him: http://tcfeline.com/2012/04/27/reduced-protein-cat-food/
I'm not sure what recipe to follow now though, since he won't touch raw and I personally think at his age it may be too stressful to force him. Now I need a good cooked recipe for cats with kidney issues.
Any help would be greatly appreciated. I'm open to all advice!

I'm very familiar with the catnutrition recipe, and it is indeed a great recipe.  I follow Dr. Pierson's at www.catinfo.org since it is in measurements I am used to (I'm in the USA).  Dr. P's recipe is based off the catnutrition.org recipe, actually.  I wouldn't bother with the psyllium though, unless there is a reason your cats need it.

Whole ground poultry tends to be high in bone content, so they may not go for the chicken necks.  I noticed my own cats have no interest in bone-in food since they get bone in their ground food, whereas when I first started making raw they would run off with raw chicken bones to eat them.  I use gizzards now for something chewy. 

We have cooked recipes in the home-cooked stickies at the top of the forum I believe.  Of course cooked bone is a no-no since they splinter, but renal kitties might be better served using something like eggshell calcium anyway.  Eggs are great for low phosphorus protein too.  I'm not a renal kitty on raw/home-cooked expert, but one of the advantages in a wet diet is getting water into them.  Water is very important for renal kitties since their kidney function isn't what it used to be.  That all said, TCFeline is an excellent resource and I've not heard any talk about that recipe not being OK for renal kitties, but again I'm not a renal kitty on raw/home-cooked expert.

Thanks for all the suggestions! Yes, I will probably cut out the psyllium as I looked online at a site that had comparison photos of what a cat's stool looks like with and without it. Scary stuff LOL
My cats love chewing on hearts, therefore I will probably leave the heart and liver whole to give them something chewy. I did try today to throw them part of a raw chicken thigh, but they didn't seem interested in gnawing on the bony part. They stared at me until I whittled the meat off the bone for them...spoiled little devils!
I lightly cooked some chicken and heart for my older guy and added a little warm water to it and he ate it up! I definitely think cooked is the right way to go for him. Dumb question, but do you know if I could just use the TCFeline reduced protein recipe and cook it, instead of serving it raw? Or do I need to do something different since the meat is cooked?

Hearts are wonderful treats, I wish I could get them!  Liver can get a bit "rich" for them, some will get diarrhea and some will just throw up.  There are nutritional problems that can arise from too much liver, but I think it's a pretty high amount.  Like, REALLY high amount.  They aren't very chewy, but if your cats love them then I'd consider it a treat occasionally and knock on wood, sometimes we need those beloved treats to hide pills.

I see that TC Feline is on the list for home-cooked, so I don't see why you can't just cook the meat and add the TC Feline.  Here's a thread I found that might help too:  http://www.thecatsite.com/t/266872/home-cooked-for-crf-kitty.  Also in the stickies there are a few premixes specifically designed to be used with cooked meat like U-Stew and Balance-it.

Thanks again for helping me! I think that I will try Dr. Pitcairn's Feline Renal recipe from the thread that you suggested. That one looks like something that my old guy will enjoy!
Once I again, I can't thank you enough for offering your help and advice.

I'm sure that I will be back if I have more questions!