I think I know why they are so confident now.
apparently one of the insiders has leaked that the Orioles will get a "last-chance" opportunity to beat the highest offer, as some sort of "hometown advantage". i mean like right before he signs the contract, he'll approach the O's and say "I'm about to take this deal from *insert team*, can you beat it?"
and they are mixing that with the "Angelos won't dare lose him to the Nats/Sox" angle, and they are convinced that no matter what, the Orioles are going to outbid whoever the high bid is, at the very last minute.