Possible stage 3/4 kidney failure, please help, I am desperate

Hello, I will try and make this breif and give as much info as I can. Thao was diagnosed last year with Asthma and Hyperthryoidism. He was always a bigger cat (maine coone) we did check him for heartworms and heart failure at the time of diagnosis for asthma and since he has been on his asthma meds (flovent) the asthma attacks have stopped. He used to chew his arm before we diagnosed him with hyperthyroidism, the chewing stopped after we started his meds for a while. At this time, his kidney levels were slightly elevated, but dr said we needed to recheck them after the hyerthyroidism got under control. I failed him here, as life got caught up and I simply forgot about this. Flash forward around 4 months later (Thao is 10 12 March 7th), Thao's mother died Nov 2nd (11) from a flipped lung that caused a heart attack (need to udpate my previous post on her as we thought it was an asthma attack). 2 weeks later I noticed Thao had broke his toe so we took him in and was put on anitbiotics and ended up having his toe removed. He stayed in the other room a lot, i assumed related to pain and just dealing with his toe. He had diarreha after surgery so he was given some probiotics (he has recieved these before) and I did notice his poo went back to solid, but he strained when I saw him the 1 time (about a week ago), didn't think much of it as he just had the meds figured it was from liquid to solid, it wasn't hard figured I continue to watch it. Well I did not notice him using the bathroom (I  have 4 cats) and it didn't cross my mind as I have a 2 yr old and work full time, I don't always catch them using the bathroom. He has ALWAYS had a great appitite (a little too good), I had switched them to the Pea and Rabbit formula Septish (maybe august) last year as that seemed to be the best fit for my whole household, as we are running into some stomach issues. One of my cats recently got diagnosed with diabetes so they started getting canned cat food the middle of November. When I bought can canned food, the vet had recommended Fancy Feast, I looked at the ingredients and forgetting Thao may have kidney issues, I picked up fish, as it didn't have poultury which Thao is super sensitive to (gives him diarreha). I did not think that the phosporus level and his kidneys. So here we are 3 nights ago, Thao didn't finish his canned cat food, first time ever. They get 1/4 of a can twice a day each, I sit with them to make sure they all get their seperate amounts and Thao doesnt run the other ones off to get their food. So very weird he didn't finish his food. I woke up the next morning to him throwing up, he tried 3 times, I have never even seen a hair ball from this cat so very weird. I scheduled a dr appt. When we got in we noticed he has bruising on his eye and his belly and the base of his tail is all mild red. Dr. thought it was liver related, failure/cancer or an autoimmune that just started. She drew blood gave him vit k and gave him steriods, thinking liver related. I brought him home and since he has gone down hill. He has showed less interest in his food (can hardly get him to eat) but I do see him drinking. My house stays very much the same all the time, I do not introduce new foods/plants/chemicals. I am the only one in the house who takes meds and it is very rare, and no time recently, I am not concerned that he could have swallowed a pill. Nothing makes sense why he has declined so quick. His symptoms are very similar to stage 3/4 kidney failure. I dont have the actual numbers but vet said; liver looked good, kidney showed issues, platelette count wasnt low enough for his bleeding so she had them rerun those as they were low but not low enough to cause what we were seeing. He may also have a start of diabetes, but was hard to say if it was stress related when they drew blood and she wanted to retest that. I am at a loss.... he has declined so rapidly. Does anyone have any advice? I hate my dr gave him steroids now, as I have read that isn't good for kidneys..... I think this coming out of the blue made her think it wouldnt be this, since he hasn't been around toxins....

I have seen him drink still, and last night he did lick his pea/rabbit special protiene canned cat food...Vet isn't in til 1 today, so not sure if I should drop him off early or wait til 1.

Vet place called my vet and she said to bring him in to get vit k injection... please any good vibes/prayers.

I hope the vitamin K helps! for Thao

So he is at the vet, they are texting with my regular vet on what to do. His vitals were for the most part stable. His temp was a little low, but it is cold here and he didnt like me having the heater on full blast bc of the sound so i kept it quieter to keep him calmer, also his breathing was heavy and in his belly but he wasnt breathing from his mouth and that could be explained by the car ride and him being worked up a little, I do think his breathing may have been labored at home too.... so they are doing the vit k to try and stop any more internal bleeding and may do iv fluids... but we are on that fine line of he has low platelets and iv fluids will thin out his blood more..... so lost on what is going on. I have a feeling when he has surgery around the end of Nov, though they use the most easiest to break down drugs, I think that kicked his kidney's into where we are now.....

He had a rare reaction to his hyperthyroid medication. He did not have liver or kidney failure. He did have asthma and heart enlargement and got to the point he was having issues breathing. He was having other issues w lack of vit k related items. He stabilized and we transferred him to an overnight facility and the trip was too much, we felt we had to try. We didn't think the trip would do it to him, but it was that or put him down then and there, he seemed more stable slept a little I couldn't put him down at that point. Posted his pic on the crossing the bridge board.

I'm so sorry, kittiekitten, it sounds like nothing you could do could change the outcome, you DID do everything you could do.  Your sweet Thao had some very trying health issues, but he was quite the trooper through it all, he knows how much you wanted to help him, he knows how much you love him.

(((HUGS)))