I’m guessing just a funny translation thing. Even here in Canada, where French is (slightly) more common, I often hear the dip referred to as “au jus.”

I speak some French, and can grammatically attest to saying “with with juice” is wonky, but I’ve been reminded by a couple of equally pedantic well-trained chef friends.

But I also didn’t mean to cause a hubbub!

Call it what you will; just don’t call me late for dinner!