Consider too that if Kerry's own statements about being responsible for his own acts of war crimes is true, then his crew would be guilty too, and thus have motives for their support of Kerry. I'v heard mention that at least one is a paid member of the campaign staff.
I think the paid member of the staff is Skip Barker, an officer. I haven't heard of any of his enlisted crew being part of the campaign managers. The enlisted guys who travel with him must have their expenses paid by Kerry however.