Yeah, I'm not sure there is much to be gained from leaking internal data (are DMs that valuable?). The actual scam is executed so poorly that it can't be the main goal too. "Prooving" you have a good exploit by throwing it away is also not plausible.

There is a spike of the short volume on 8th - https://fintel.io/ss/us/twtr

Bad idea for the hacker. Stock ownership is public information.

Doubt it, that would open up too many vectors on an otherwise easily anonymized operation.