Technically

Wdym

Constitution doesn't state anything about running for office.
22nd Amendment could be repealed.
It could be revealed that any Amendment ratified after a certain year, like 1871 or 1913, is voided due to illegitimate corporate government takeover of the United States.
Trump could just run, win, EC elects him, SC sits on their hands, and nothing happens and the people move on with their lives?
There's more scenarios...

You can be President without being elected too.

He wont even live, but there is 2 amendments in his way

Why wouldn't he live? Biden is older.

Bullets.

My my.

Ask the Jews what happened after Germany took away private guns.

Biden and Trump won't survive until 2033