I'm playing through SA again for the 3rd time, but this time with mods. I'm having a blast with this game as always, but last night when doing the mission Pier 69, after killing T-Bone Mendez, I got out my rocket launcher to try and stop Ryder from escaping. I fired a rocket at him, but missed and destroyed his boat instead. He couldn't get in the boat of course, so he swam to the island and just stood there waiting. I swam to the island, got ashore, walked up to Ryder and shot him with my pistol several times. I killed him in a more conventional, realistic way, rather than in some high-octane speed boat chase and explosion scene out of a Hollywood action movie.
Never knew he could be killed this way! Just thought I'd share my experience! Lol