He was recalled after the roster freeze was in place which would seem to imply some sort of complicity on the part of the recalled player.
Something along the lines of "if you accept the recall you're also agreeing to a potential subsequent reassignment within the roster freeze period"
Detroit sent down Kris Newberry on the 21st--after he played in an NHL game on the 20th. He had been recalled on the 14th. The roster freeze starts midnight on the 19th.
The CBA says players can be freely recalled during the holiday freeze but not assigned/waived/traded. I'm guessing the "assigned" portion has since been removed or modified since the CBA was written. Perhaps only for players that can be assigned without requiring waivers.
What you'll notice looking at the list of past winners is that winning the Hobey Baker is no indicator of NHL success. Most of the sure fire NHLs, if there is such a thing, come out of college to go pro before they get a chance at the Hobey Baker.