How are they gonna prove he's not dead?

Have him write "truths"? That's just an LLM That's trained to sound like him.

Get his voice somewhere? They just fed that LLM into an AI voice cloner.

Video? Ok so they added deepfake into the mix.

Short bits of him leaving the White House from afar? Body double.

He needs to travel the country doing rallies twice a day and shaking hands with all the people so we can actually see he's alive. Anything short of that is just unconvincing.