I think it is simply that he does not want to pile on and make it look like it's politics.
I could be wrong of course, but I think that could be the reason.
It was his job to appoint someone when Reiner's term expired. He didn't do it in 2003. He didn't do it in 2004. He didn't do it in 2005. And now he won't even comment on it. He's not doing HIS JOB!