You can count me as one of the nodders here! My vet almost killed my cat!!!!
I am not up to date on Chester, but from what I am reading I will share my thoughts. I am assuming that Chester was eating dry food and that you made a diet change to wet Low Carb food. If that is the case, that can make a tremendous difference in the blood glucose level. Most of the cats, that I have witnessed, that came here and went off insulin (OTJ) quickly-- were cats that changed from dry to wet low carb diets. I have seen such diet changes, result in as much as a 100 point drop in blood glucose levels.
Since you have shot no insulin this cycle and just fed Chester, this would be a great time to test and see if the Pancreas is helping out. If you will test in one to two hours after feeding, and the BG is coming down without shooting insulin, it is fair to assume that the pancreas is producing insulin. I would test in an hour and see if you have a lower bg reading than before feeding. It would be great information to have.
I am not the person to give advice on shooting low doses of insulin into numbers less than 200. I have no experience with that and am not comfortable advising you, but if you continue to see numbers in the high 100s, you probably will need to do some micro dosing to bring the numbers down futher. There will be others that can help you with this dosing advice!
You are in a Great situation! Hopefully, the pancreas is trying to help you out!
Good Luck!