He developed Stevens-Johnson Syndrome which is itself rare and is, rarely, associated with other vaccines as well. I saw it once with a young child who developed it after an antibiotic back in 2004.
That will probably not happen. Instead, "You participated in an experimental vaccine, so no compensation for you!"
I have had SJS more than once. Fortunately it was confined to less than 30% of my skin. It is horrible, painful and takes a long time to heal.
I was thinking of getting the J&J vaccine...hadn’t decided yet. This was the reason for my hesitancy. I think Moderna has caused similar problems.