can you find another job... and/or does he make the recommendations?

Does he care what anybody thinks? How miserable is he? Or not?

Does he have any vacation time accrued so he could take time off and think about who he is and who he wants to be?

There are lots of people in this situation taking the path of least resistance. Can you think creatively and perhaps brainstorm a way to make the path of least resistance less desirable?

I don't know if it applies in this situation but in my jobs one part of these kinds of situations has been "document, document, document." So, letters of concern might be more effective than mere words? Letters that are completely fact-based and objective... but make it clear that Somebody Has Noticed a Problem, so if it Blows Up In Your Face You Will Look Irresponsible...?

This has got to be painful for you and all concerned :*(