Michael Cohen, the archenemy of Donald Trump, was set to be the star witness at the ex-president’s ongoing bank fraud trial.

But Cohen has surprised the New York Attorney General’s office by potentially canceling his court appearance next week—citing a medical issue, according to two sources familiar with the situation.

Cohen, once Trump’s trusted legal adviser, took the fall for the former president’s hush money payoff to porn stars Stormy Daniels and Karen McDougal, among other things, and spent a combined three years in federal prison and under house arrest.