I have a BowTech ExtremeVFT, I shoot gold tip XTs with 2" Blazers. There definitely is a clearance problem with the cables when shooting cock vane up or down. Solution: Shoot cock vane out like we used to do with fingers on the old springy rests. If your rest allows you to rotate the nock so the cock vane is pointing out from the riser at a 90 degree angle you'll be all set.

Oooops, my bad. just re-read your post about the rest... If you don't have any luck with the cable guard change, maybe changing the rest is in order. I'm shooting with a DZ and rotating the nock resolved my issues.