So I accidentally sold the token to speak with the mystic lady in Whiterun because apparently this is not considered a quest item. I can't get the ancient shrouded armor now because of this. Is there a way to get a new token? I did the bonus part of the previous mission.

Looks like you can't ever get it again, the ancient armour is like 10x better than normal, so you should re-load or something.

I have no clue but did you try to pickpocket her?