As for Flynn's entry, my thought would be that he arrived on the island a day or so ago, and has been doing some basic checking around- local rumor mill, that sort of thing. He is quite pleased to have finally tracked Kat down, but wanted to know the lay of the land before making his approach. While the exact object of the mission might not be known, it probably is known that Kat is seeking a crew. There are, after all, at least two groups that have been recruited already, and I don't think the drunken Latvians are likely to be too closemouthed. It is, therefore, likely that Flynn is at the Blackreef tavern, waiting. (For a suitable moment, of course...)
BTW, weren't you all going to meet Blackbeard sometime soon, to try to negotiate a 'change of ownership' for the Coral Curse. I thought I saw something like that (and that he might be at the tavern, tonight)- but there was, after all, A LOT of stuff to read through. Perhaps it might be good to gain official ownership before dealing with the bad mojo...