I know nothing specific about the issue per se, but I am convinced that Andy Jassy is speaking the truth here, for two reasons:
1) I've never seen a company as obsessed with security as AWS, and/or with such a big budget for security.
2) There's so many actors/employees involved in the audits, security, etc, that convincing some of them to "hide" a fact like this would be just too risky for a company that big. If that were really the case, I would rather work on a contingency plan, assuming that sooner or later the "leak" would come out.
There is a tiny chance that something bad happened, and that Amazon's magic PR twist managed to still provide a truthful statement (Steve Schmidt) while hiding that. "A chance", because of the various back and forth business between AWS and Chinese companies. "Tiny", because other scenarios are much more probable and plausible.
This looks like a very poor example of journalism, on Bloomberg's side.
On a different note, I still believe that weird/illegal stuff keeps going on between companies and governments worldwide, for the simple reason that these things keep coming up when there's a new leak, or when secrecy on certain classified documents gets lifted or expires.