I believe Lindell himself just went with option 2 in your list. (Hackers/Antifa implanted a worm or virus or something that if he were to move forward and show the world his evidence, it would blow up and he’s not going to endanger the safety of everyone present.)
PS. Buy my Pillows.
Hmm. If Lindell’s cyber experts aren’t familiar with the concept of backing up files, he’s really in trouble.