Obviously, you already know the significance of an increased BG so I won’t address that. It’s possible his albumin, hemoglobin, and hematocrit are elevated because he’s dehydrated. Dehydration often presents itself in higher levels of those parameters. You might work in getting alot of extra water in his food.
His ALT, which is a liver enzyme, is mildly elevated. There are alot of reasons why ALT can be elevated; but, just to give you a frame of reference, even three times high normal is still considered to just be moderate. ALT has a short half life and so you might find that it changes quickly. I’d discuss with my vet giving your little guy some liver support supplements like milk thistle. While Denamarin, which is milk thistle, is the usual thing they use, I really like Herbsmith milk thistle powder. I get it at Chewy.com and find it is much easier to administer.
And finally, his potassium is low. We can see low potassium in diabetic cats due to insulin causing it to be taken up into the cells so that the serum level is lower. However, his is a little lower than we normally see in FDs. I’d discuss this with my vet because you have to be extremely careful with potassium supplements. Too much or given for too long can cause alot of issues including heart.
I hope that helps!