Aaron Zelman died in December of 2012. However, I concur with you about Larry. He is definitely NOT anti-Semitic.
Since he must know about the host of the event - he is no fool - how can you be sure of this?
Sorry, but anyone who makes an appearance at an event sponsored by an anti-semite is not someone I could ever give a pass to. If Pratt was making an appearance at an event hosted by someone outspoken for abortion, would you still give him the benefit of the doubt?