If I were stuck on a dinky life-raft, which met this other life raft with another person and an injured guy. I wouldn't eventually just untie the other life raft (now taking on water) go even if the injured guy gave me his blessing. I'd drag him into my boat whether it hurt him or not.
This may seem exceedingly moral, and I certainly wouldn't tip my hand in that regard. If a rack of lamb wanted to float away I wouldn't let that happen either.