> Unless Elon's statements were actually truthful, it seems that his comments fall under two or possibly three of the above categories. (depending on how one interprets the email he sent to a buzzfeed reporter)

Actually, I think it potentially hits all four:

Pedophilic acts are generally crimes, and the totality of the circumstances makes it reasonable to conclude that Musk meant that acts, not just orientation, is involved, meeting the first form of per se defamation.

Pedophilia is a diagnosable mental condition, and one which brings significant social disapprobation; mental disorders have in some cases been held as being “loathsome” diseases. To the extent that Musk's claim can be viewed as including (even if not limited to) a claim of pedophilia in the sense of the disorder, it fits the second category.

Pedophilic acts are also sexual misconduct as well as crimes, so it fits the third category for much the same reason as the first.

Accusing a professional cave diver currently employed as such in a rescue of children of being an active pedophile certainly seems like it is accusing them of something incompatible with their business, trade, or profession.

(Huh, this case could become a new textbook example of per se defamation.)