Poor guy. I'd say he was less stressed today if he was playing. Most cats don't like quick movements or loud noises. Neither of mine do. They growl if someone rings the doorbell. They don't like company. Moonie will stay out and socialize sometimes, but Basic doesn't at all.
You're putting the cart before the horse, friend. May want to take that pressure off of you both (remission). Keep in mind, some cats don't get regulated. I was making myself crazy until I stopped making either my goal. I just focused on getting his numbers to a point that were out of the 400s, then the 300s, then the 200s, etc. It helped remove unnecessary pressure that I put on us both.
Libre would certainly give you more readings because it is always monitoring. You may be able to switch his dosing protocol if you have the numbers. It can be a little scary. I think time will tell with him if that would be an option for you or not.