The party was being trailed by a spy, but they caught him and disposed of him. Then the bard used disguise self to report to the spy's superior and convince him that the party wasn't a threat (which the bard did through good preparation, good roleplay, and good Deception checks).
The party has played the intrigue game very well, eliminating all possible threats and covering their trail, which is why I'm hesitant to toss all that aside and just drop an ambush on them. They've done everything they could to prevent a battle, and I haven't exactly been treating them with kid gloves.
Anyway, the party is returning to the adventure site next session, so there should be more action next week. I'm just not sure how it will all play out, with the group divided as it is. Two of the players want to talk their way into another meeting with Bad Guy Leader so they can capture him (presumably without a fight). But one player, who has already said he doesn't want to kill any Bad Guys, is clearly put out by this plan and wants to side with the Bad Guys. So group tensions could come to a head next week. I hope not, but that seems to be the way things are headed.