Here's my take. Scathan had to step in not because LT would've gotten beaten but because LT and LT copied Protege would've been an eternal stalemate. Which might explain Scathans presence, perhaps only he has the ability to nullify the LT's power. But, I believe in the grand scheme of things the LT is above Scathan as far as control. I think that the LT could judge against Scathan and sentence him.
In terms of power on power? Can't argue with on-panel feats. Scathan defeated what was, in essence, the LT.