Daniel Gildenlow was willing to come to the US for Gigantour 05. As you may have heard, there was a communication breakdown between Dave's management and PoS's management: PoS never received the offer, so Dave had to assume they weren't interested. When a fan contacted Daniel Gildenlow to ask why he said no to Gigantour, Daniel said something like: "What? They asked for us? We never got the offer... but of course we'd be interested and we'll send a message to Megadeth's agency now." (We believe there was an email malfunction). By then, of course, it was too late and the tour lineup had already been solidified, but the most important thing about that was that for the right offer, Daniel said he was willing to come to the US. Given that he has a person-to-person working relationship with Glen and he knows Glen is not "big-Bad-USA", I think he'd be willing to put aside political hangups to come back for us PoS-starved fans in the US.
afterthought: i believe this was after his dismissal from The Flower Kings for said political reasons.
My headliner predictions:
Friday - Symphony X
Saturday - Gamma Ray