Can-Indy-Jam, if they were going to request his departure by a specific date, they would have asked for a travel itinerary when he brought in the PP. Remind your husband that if he shilly-shallies around, the visa WILL expire and you will have to reapply and go through this process all over again. I don't think either one of you wants that, so get his ticket booked to get him into Canada for landing ASAP. He can always come back to Jamaica after he receives his PR card to tie up any loose ends, if that is what he is worried about.
Possibly because your husband's medical has more than 30 days validity left on it is the reason they didn't ask for an itinerary. For most persons whose medical expired in less than 30 days after the visa was issued, they have requested an itinerary with a specific deadline.