Unfortunately, jerks can buy and run a game as easily as everyone else. So you have to expect a lot of the trouble you're having, it's pretty much unavoidable.

The party finder does help, but it could take a LONG time to get a party together. Posting up something like "first time run of Aurum Vale, lookking for help" or whatever coud work for you. As I said, it'll take forever to get a party, but you'd know you're getting people who are willing to help you.

It's up to you how you want to weigh the convenience/speed vs. pleasantness/fun factor.