SUCCESS.
After all of this, it ended up being a vane for the leveling system that was about a half inch more recessed in penetrating the Banner unit, and was breaking one of the bridging switches (KUET and KUET1)
Adjusted the vane plate out a bit and haven't had an issue since. for anyone fighting with this problem in the future -- pay attention to the hex codes! the T4 error gave us the car height in mm, which told us which floor, and the KUET fault pointed us to the bridging contacts in the PHUET banner unit.
