While that may be the explicit language for the charge, the feds don’t really tend to execute people in the modern post-Gregg era, with a notable exception: Donald Trump restarted executions from the feds when he took office. So, slight correction to my OP. I guess it would be possible, but I highly doubt the US Government would do something as drastic as executing a previous president.
On a personal level here, I am 100% against the death penalty. Even for fucks like this. What’s worse, death, or living your final years in a concrete box and dying there instead? I’d much rather people like him get lost in their own thoughts.