Its sounds like you are making the situation more complicated than it needs to be. I used to have 2 AP T3's, and I used the belly heat option for them, and that worked fine. Just for kicks, I also ran a overhead heat source to see what would happen as well. The overhead heat source worked fine on its own. If I were you, I would place the Johnson Controls probe inside the hide on the warm side, and use the ceramic heat emitter to create a basking spot of 94 inside the hide. With temperature in the 90s in the warm part of the cage, that should translate into about 80-82 on the cooler side of the cage without having to use any flexwatt. I'd try that before you pull out any more hair over this.

If you do that and think that your cool side is dropping too low, go ahead and hook the flexwatt back up on the cool side.