Odell was on one of three boats when Kerry pulled Rasmussen out of the water. 1 boat was hit by mine and blown out of the water. Odell's boat stayed to pick up injured. No fire from banks. Kerry fled the kill zone. Rasmussen fell off the boat when Kerry sped up quickly. Kerry turned around to pick up rasmussen, and then continued leaving.
If I understand correctly, Kerry's boat was the only one to cut out and run. I didn't remember that Rassmussen was on Kerry's boat. I guess some remnant of humanity compelled him to return. But he got to Rassmussen just a moment before another boat reached him--one which had not cut and run.