Westwind aircraft have two storage lockers that are only axcessable from outside the aircraft. Rafts are never stored here. The raft would have been placed near the door. But with the main door opening on ditching. Chances are it would have moved .I would expect the nose would have sunk quick also. 3 minutes to sink indicates to me that the foward cabin area would have been under a lot quicker. Add darkness, wave chop.ending up with a lost raft would not be impossible. My guess is they all would have been told to grab there vests. Some may have missed this in the panick.
Just my 2 cents