Most Helpful Guy
Why doesn't she move to be with him?
If they're getting married or on track for it, and it makes more sense to move to where she is, yes, I think a fair number of guys would do so.
To just randomly move messing up his career for some girl who is not as into him as he is into her... some guys would do this. guys who are inexperienced, lack awareness of options, and they'll regret it later.
Most Helpful Girl
The girl should let him wait, she should let him take the job. At this age, we all need to take every opportunity we can grab to progress our lives and careers. If he doesn't take it, he's only thinking of now not of the future. If she also wants a good future, she should factor in both, not just relationship.