Delorus really should be level 16, there's no reason why he should be level 9 here except to make this quest a trap. By that I mean, this quest is intended to be failed unless you specifically clear out all obstacles and enemies.
It's pretty pointless that he's level 9 because most people will just do the exact same thing I did: Encounter him, have him get killed in the first battle because he's hopelessly weak, then reload and completely ignore encountering him until you clear the path, after which there is no challenge to it.
If I understand correctly he did not ressurrect him?
I don't think you do, otherwise why would he mention paying for a half-dozen resurrect scrolls.