[quote=Ruby]
"Using technology available to him in the future, Bishop constructs a time travel device. A device that, despite the technology of his future, can only provide a one-way trip to the past."

Solved. The bigger issue, and why we wince about time travel, is what happened to result in Bishop's future? Xavier's already dead. So it can't simply be that. Maybe...for some unknown reason, this team failed? Or, even better, maybe this team couldn't get to Fury in time to prevent HIS death? That'd work better for me, and will solve for me, the storyteller, how the team learns of Fury's detained location.
[/quote]

Please, let's NOT get started on temporal mechanics. :newlol I'm too much into time travel (hence why I like Bishop) and could probably write up an essay for you on how both the successful and the failed future exist at the same time. :confused

As for the story, sure, you can use Bishop as a McGuffin. The original Bishop did grow up on the old stories of the "Legendary Team" of the X-Men. I cna't see why we can't tweak it a bit to include a team of both X-Men and Avengers, and of course, Bishop wouldn't be privy to every single event of the past, mostly just the large scale events (and even then, just brief summaries) and the main reason why he would be in a mutant concentration camp:the death of Fury.