“Oil gevalt”. That’s something I hadn’t heard before. It looks like I need to watch The Daily Show and catch up on this “new phrase”. I enjoy Jon Stewart very much, but I haven’t seen The Daily Show in about a week now.
Anyway, my guess would be that Jon is playing with a Yiddish expression in this case — a Yiddish expression that has come into English (American English, anyway). That expression is “Oy gevalt”. In the suburban New York City area you can hear quite a few expressions of Yiddish and/or Hebrew origin.
And the Yiddish “gevald” is surely related to the German word “Gewalt”. So, yes, there does seem to be a connection.