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He dropped 5 of his 6 books on death (might be rng though?). Was able to complete the quest and loot him right away by teleporting him to his destination then immediately attacking him with a scroll. Once dead, I could teleport his corpse back to me and loot it then trade the gloves to a party member to teleport me back up and go on my merry way.
Before completing quest, give him 100 gold to get to 100 attitude. Then buy 3 books first from him. Then kill him to gain the other 4 aerotheurge skill books + Gawin's Robe + 200 XP for kill. You won't get the money back, but it's def a discount.