FictionOnlyReader
Well... Dumbledore digging up a few of Quinn's secrets was pretty much guaranteed. I don't think Dumbledore see's Quinn as an evil wizard though. All he's shown up to this point- Labels Quinn as a extremely competent social/magic genius; while displaying Moody levels of paranoia. Chances are this just means Dumbledore is going to try harder; to get the Wests involved in the Light/Dark War. All this means is Quinn's either going to take a side... Or make like the Goblins forming his own neutral group; out for his own personal gain- So basically nothings changed really. Quinn's just got to stand his ground.
Quinn asking for the parchment was too over the top. Dumbledore knows that Quinn would be able to remember every name with his confirmed mind magic attainments. It's like Quinn messed up in his acting by trying too hard. (With this even without the chalk powder Dumbledore would have had reason to be suspicious)