My read on this was that it was a snarky report done in protest. Ken Klippenstein is a troll who does things with a straight face, and likely so are people who leak to him. I don't think anyone really believed it was hacked, but rather it was a way to criticize it with plausible deniability.
The article includes a screenshot: https://assets.documentcloud.org/documents/20532639/amazon-t... Seems like a lot of detail (e.g. going back through the past 2 months of tweets to check the source label) for just a "hey this sucks!" protest. Also, seems risky to send a screenshot of your own ticket while logged into the ticket system, though maybe all the login template info is just outside of the cropped screensho…
FWIW, this is how much detail i'd put in for the plausible deniability "this sucks" protest if that were me.