I agree with ScottG. There was a post last spring, I fellow included pictures of his linoleum flooring. The crack was full-length, front to back. The extremely cold winter had shrunk the frozen flooring, splitting it wide open.
I really don't think the crack you have is anything more than a similarity. I would plan on installing an interlocking laminate flooring over the top of what you have today. Just consider that expense in your offer. A laminate floor is an upgrade when buying a new rig so it is a common application.
Laminate flooring is easy to install for the novice, the floor rests right on top of the vinyl floor, no adhesives, just lay it down and install base shoe around the perimeter. You will need to add some kind of trim for the step-down into the cab and also for the main entry door.