There is no evidence of that whatsoever.
But as you state your belief, whether you acknowledge it or not, you agree with my proposition.
There was no reason for him to go off on Jews.
He blamed Jews for wars. That war was on his mind is possible. That Israel was on his mind was possible. And like for all anti Semites, so was the usual scapegoat on his mind.
There was no slur involved. Only a demented bigotry freed of the usual social constrains by the alcohol he had consumed.
Which is why he will now become a large hero to the usual haters. A hero for speaking the "truth".
Anybody want to start a pool on the date of Pat Buchanan's Gibson-apologia column?