I would be quite concerned if a snake's jaw remained unaligned for 4 days straight. Also, he should not be getting anything into his mouth unless during feeding, and he should have no trouble working anything out of it within a matter of hours. Now it's somewhat difficult to say in black and white what you should do, not seeing the degree of the jaw misalignment first hand nor the certainty of what was actually inside the mouth.

Personally, I would only go to a vet when I was certain it was something major. My observations would contribute a large deal to that certainty though. If it were me, I would take a look inside the mouth and go from there. However, I'm not about to go about telling other people to pop their snakes' mouths open and prod around inside it. It's not particularly difficult to do, but there's always the risk of injury if something goes wrong, especially if something may already be wrong in that area.

Therefore, I'm going to suggest you take him to the vet. So, treat my vote in "Yes, that sounds correct. I wouldn't take him to the vet." to "It sounds possible, but I would take him to the vet to make sure". Of course, with all that said, you should base your final decision on what you have seen yourself from your snake, and how confident you are in whether or not you would be able to spot if anything was wrong yourself.