Here is another thought… over tightening the bearing cup will change the amount of pressure applied to the bearings when the crank is nipped up. I dont think HT 2 do well with side loads along teh crank spindle. (hard to explain..)
I bought a GUB bb from China. Standard spacer fit is 1 on the Non ds, 2 on the Drive side. Did this and no way would it spin. Took one spacer off the ds and checked the Raceface splines were “just” appearing through teh plastic bearing cap. RF has some small thin washers and using these I managed to get it bob on so that when nipped up, the crank spindle has minimal compression loads into the bearing, and its working perfectly.
So it may not be your bike but teh way teh HT2 is set up…?
HTH