Maybe, maybe not.
The only predictable thing about Trump is his unpredictability, which he uses to his advantage.
“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.