I'm sure it was watertight and full of elaborate pilpul, but Trump should have just said no to the courts. Unfortunately this is one of his weak spots. He personally doesn't understand the law, and was surrounded by bad or malicious advisors. (Bannon was the last good one IMO) The uniparty had an army of attorneys working against him to make sure he was ineffectual.

That said as other comments point out ignoring the courts would have been more ammo for the impeachment.