I'm also interested, I've been reading your comments, until now I've done the same actions and still no heart with that despicable man, I don't even know if the game allows it at the moment,however if I manage to get something I'll update too.
Hmm I was told it was possible but we still don't know how to achieve it..
I remember I got gunnar's heart in Northcrest but I don't remember how I know I will bump it on a weekday