Detached Garage Sinking?

Two questions:

1. Is this a dangerous problem?

2. If it is, do I have any recourse having just bought it in August?

Full context: the concrete is busted up bad on the garage floor and we don’t really care about that. The inspector noted it but didn’t mark it as a structural concern. The human-sized door worked fine all last year. We didn’t use the garage in the winter so didn’t use the door. In the spring, I noticed the door was jammed and found it was because it now had an angle so severe that the deadbolt wouldn’t line up anymore. It seems like that side of the garage sink down at least an inch or two.

It is an old home (over 100 yrs) and the home itself shows no concerning signs. Everything seems pretty much settled, so this caught us by surprise…especially the speed of it and that our inspector dint have any concerns. We’re planning on replacing the whole garage at some point (in a few years though) and hate the idea of repairing this unless it’s actually dangerous. But to talk to a structural engineer, we’d be out $700-$800 right off the bat. We’d have to pay for the whole home since they won’t reduce the price for a simple detached garage.

Wwyd?