It "feels" like an insider attack (simultaneous compromise of lots of high value accounts) but I agree, it will make for a fascinating post mortem if one is produced.
And now this : A Twitter insider was responsible for a wave of high profile account takeovers on Wednesday, according to leaked screenshots obtained by Motherboard and two sources who took over accounts.
Hmm, how much money this scam would potentially generates? I think the salary of an engineer working on twitter would be higher given how fast this scam would be shut down. Would a twitter employee risk their career to this scam?
I would be surprised if it were an engineer, but not everyone who is employed would be an engineer. When I was at Google two fairly high profile incidents were enacted by contractors (one in the IT "TechStop" group and one a data center tech)