Chuck Murray
WIS & Effingwoods Hockey Almanac
I'll assume, taking into account all that I've heard of Barr, that there is a level of ambition involved. I'll also go waaaay out on a limb and assume he "decided to play at RMU" because the other option was DIII. Not that there's anything wrong with that. So give me a scenario where "you" would rather play at RMU? You mentioned being happy with his educational route. If it's all about the diploma and not the hockey, why not stay at RMU for the last year since they will be honoring schollies? Aspiring to be RMU's last ever captain is indicative of a lack of hockey ambition. See my first point above.
FWIW I think his agreement to entertain coming to UMaine will carry the day. You make an important decision like that, and you tend to turn the page on your prior station. If you've got a steady job, but you're underpaid and/or underutilized until someone else comes in with a better offer ... and then, on notifying your current boss that you're moving on in two weeks, the current job belatedly offers you a promotion and a raise ... you've still told someone else you're leaving to come to work (play) for them, and it took you putting the proverbial gun to your boss' head (in their eyes?) to get him to offer you a better gig. Not exactly the same as what we have here, but the same principle is in play.
Some folks will see value in staying put, naively trusting there will be no retributions, while I do think most folks would end up following through on their promise to start fresh at a new destination. Personally, once I started that train moving down the tracks, it would be tough to back the caboose into the old roundhouse. But that's me (and presumably you), not everyone ...