Whatever the reason was, the bottom line is that he was still there because they didn't vote him off. Does he really think that the other tribe won't vote him off first after the 3 remaining members of his old tribe are gone? I can't imagine him ever winning immunity.
His next move should be to align with a couple of people on his "new" tribe along with the 2 remaining people of his "old" tribe and shake things up again. Maybe vote Coach off this time?