I'm glad to read that you have caught up with sleep, and that Sandy is doing well, even jumping up on the counter.
And especially relieved to here that your family member has only had mild covid, and recovered well.
I laughed when I read that Sandy and his pal have taken over your sons room.

but it does give you some flexibility. It's hard work being the food police. George is 21 so now he can't jump on the counter, so I have a spot where the young ones can have some food out and graze, so I don't have to be on 24hr waitress service, at night George sleeps on his own (he prefers it) the others are all together.
5 large dogs and 3 more cats
I'm guessing the dogs eat all their food up so that won't be an issue LOL
Any suggestions on kibble he can have? I’ve heard young again? I forget who makes it.
If you have cats that are kibble addicts or you want to have something to leave out at times then Young again is an option, Dr Elseys, and Ziwi peak, all do some dry that is low in carbs so it won't be a disaster if he were to get into it. ( we don't get any of those here in europe so I'm not the best person to ask.)
Personally
On a good note, I’m putting out wet food in the main feeding area too and my other cats are absolutely loving it!
I like this option better, thats what we have done all the kitties are on a wet LC diet. They only get kibble when we go on vacation, because the cattery won't feed them wet.
You probably haven't read this post by Dr Lisa since you have had you have had your hands full since you came on your board, not time for sleeping much less reading!
https://www.felinediabetes.com/FDMB...r-more-than-just-carbohydrate-content.175004/
Dr Lisa also has a feline nutrition website
https://catinfo.org/
Sandy’s numbers have been good. He’s had ff gravy couple of times because he didn’t want to eat the pate and it’s clear that makes his number go up some.
After his number domes back down to normal numbers.
You might want to experiment with some different flavours varieties of wet food and rotate them, although kitties will eat the same brand dry day after day, with their wet they seem to like a change.