“We’re going to be appealing the gag order. I'd love to answer that question, it’s a very easy question, the easiest question, but I’m not allowed to testify because this judge, who’s totally conflicted, has me under an unconstitutional gag order.”
Oh I see. Trump actually means he's not allowed to answer the question about testifying. Of course he can testify in his own defense, but I'm guessing the judge - in his infinite lawfare - has ordered Trump not to even answer a question about testifying.
He’s being facetious, sort of. Killing 2 birds with one stone.