Advice on stray/feral cat

Hi everyone, I'm a newbie to this board, so please forgive any ignorance but I could really use some advice. 

My partner and I recently moved out of the city to the countryside with our indoor only cat. This November, a young cat started coming around crying. We gave him some food and he bonded to us over a few days. We trapped him and got him neutered, dewormed and vaccinated. He's been happily living inside since. His name is Twinkie.

Now a cat that looks like his brother has turned up and crying. This cat is much more shy and has a cloudy blue eye, so we called him Winky. We built him a shelter and gave him some food. Because he didn't seem as skinny as his brother and we've seen him around the neighborhood, we thought that he might be being fed somewhere else. But Wednesday night he was attacked by another feral cat in our yard. I turned on the light and Winkie must have gotten away, but the other cat stayed for a bit so I'm sure it was a cat fight. 

Winkie's got wounds on both his hind quarters and tail and he isn't neutered. We have plans to trap him and bring him to our vet tomorrow (Saturday), but I'm not sure what to expect.

We were planning on keeping him in our laundry room/rec room away from the other cats to socialize him to humans and get him healthy and then adopt him out. Considering how beat up he is, I don't think the outdoor life is for him and we have some friends that have shown interest. 

With the cloudy eye, leg wounds, and big stomach, I'm worried about this vet appointment. Any advice?

What worries you about the vet visit in particular?

I'm worried that there may be pressure to put him down because he got bit by another stray cat. I really want to get him healthy and in a good home. 

Also, any advice on how to make this all less traumatizing for him too. 

I wouldn't worry about that. If his quality of life will be rotten, it will be better to euthanize him. You wouldn't want him to suffer. But that's a worst case scenario. Think positive!

Your vet visit is tomorrow so no time to buy Feliway spray. This is a great spray if you have never heard of it that calms down the cat in its carrier. The only thing I can think of is once he is in the carrier cover it with a towel to calm him down. I would get him spayed ASAP. And then just take things as they come along. You're doing a great thing so I'm sure everything will work out well.

Thanks for the words of encouragement. 

And thanks for the Feliway spray! I'd never heard of it but will be sure to pick some up. 

There are Feliway diffusers also that you can plug into sockets to calm things down.