Tight Regulation allows you to keep them in healing green numbers longer so the odds are better with TR for regulation and hopefully remission. It can still happen with SLGS, though not as frequently. You do test enough for TR, so as long as he's only getting the raw and wet food, you should be able to follow TR. Hopefully the next month around closer will get you some serious progress.
Note that for a cat greater than a year since diagnosis, they are considered long term diabetics, which changes the reduction criteria for TR.