1) Reb Moishe never allowed his children to eat CS. Does that mean that he didn't allow it?
2) it could be that Rabbi Werner is makpid not to eat food from other ppl.
I know Rabbi Simcha Werner well.
He is a emese ehrliche yid and a BIG yirei shomayim. and indeed, he probably won't eat anything on pesach aside from matzos potatoes and wine (yes, no oil or potato starch etc.) So to say that he wouldn't eat it doesn't take away from the kashrus of the program.