If he shows the athleticism, why not take a second round flyer on the lad? Most big men take some time to mature into their game, why not send the kid to D League and see what they can make of him? Besides, he's got one hell of a resume' as a player and it would be nice to have 340lbs of intensity in Green.
He won't be drafted by anyone. If he showed anything in those workouts, invite him to camp.
Unlikely that he would come without some sort of guaranty because of the sure-thing $$$ he can make in the CFL.
Since their season starts earlier than the NFL and ends much earlier (I think around Thanksgiving), maybe he plays the season there and if the Cs and him are still interested in each other, RedClaw him to see what he can do before any commitments are made.