Gotcha.. yea, the Rhino has no idea what is going on inside MSFS as there is no native FFB. Even with TelemFFB, I don't think there is enough data available in the sim to try to implement any sort of force-trim feature.
Is there even a 'force trim' button binding in MSFS? Admittedly I have flown very little MSFS since before they (natively) supported Helis. I cant get over that the throttle and collective bindings are still tied together so you can't even use the same control bindings sets for fixed and rotary aircraft w/o causing glitches.