So I gather his rim looks something like this one (Only the inside natters)



Rim tape isn't rocket science,and I'm having problems understanding why the OP is having such a tough time. Ideally he wants a tape that lays completely inside the lowest part of the center well. But of the holes come near to the edges, he needs to go a bit wider with something that comes up the sides slightly, but not far enough to reach to where the tire sits on top of the two side zones.

IMO- filament tape may be the way to go, with two turns, one favoring each side to give him the exact coverage he needs, with double thickness over the holes. Otherwise a urathane (or other ballistic material) band of the right width would another very good option.

Once in place, tapes don't move, unless you trap a tire bead against the edge and push them over. In fact, the issue may not be the tapes, but tight tires and his mounting technique.

Rule 37 -- if someone is having problems with something that millions aren't, you have to look for what's different.