It didn't make much sense at first, but after thinking about it I figured this: Frenzy got his head chopped off in the first movie and he lived, in the second movie Mixmaster got chopped in half and he lived... until Jetfire started chopping him up some more. Then Jetfire got gutted by Scorponok and was doing alright until he ripped his own spark chamber out. So I could easily see Bonecrusher putting himself back togeather and hiding out like the other Decepticons, then smuggling himself to Egypt to join the others.
So unless there was a Buffalo mine protected vehicle just randomly sitting around near a village outside of Cairo, I think it would be a safe bet that it's Bonecrusher and not just some other Decepticon. That and it's alot cooler to think he lived.

-Groovy
