I wouldn't expect him back for a while, and, depending on whether he needs surgery or not, and what the team does at the deadline, there's a chance that was curtains for him in the OHL. Hoping I'm wrong.
After the initial buzz of this I wouldn't be surprised if it doesn't change too much initially. The kids playing USHL also have deals there, and there are very few players that are so good that they'll walk in and bump established OHLers out of their lineups. So unless Kwajah thought moving mid-season into a D needy lineup made total sense, maybe it's next season for him.
Prud'homme might be a better candidate given he's not even playing major junior, but these private college kids... I'm sure there is a lot more going on in the background including things like tuition considerations. Doubt he suddenly wants to leave a private high school and come hang out at OSDSS or St. Mary's.
Prud'homme is also not exactly lighting up a very low level either, I'm far from convinced he'd be an upgrade on what we've currently got.