You live in a small town with one small hospital. I’m sure that you have reasons for living there, but I don’t see how you can blame your Michigan degree for your lack of opportunities . First, new job opportunities are unlikely to come up often. Second, it is perfectly reasonable for an employer to look to its own employees first to fill new jobs. They are known assets and it promotes employee morale to know that they have opportunities to advance.
As a thought experiment, consider whether a Harvard or Stanford degree would make any difference in your situation.