The official announcement clearly stated it would only be for the nano and wi-fi. That sure sounds like a "nope, BT can't have it"
I do appreciate you looking into it, but, without any official word that they might be able to do the BT, then the announcent stands and your efforts are in vain.
If for some hardware limitation, the BT actually can't work with the multi-cook function, you still should be able to give it the multi-step function. Even if the has to send a momentary stop command before changing temps.
Heck, you guys do that (multi-step for BT) I might actually take an old phone and put the app on it and start using it again.