Its pretty clear what Sandy Munro is doing however. He's trying to sell his consulting services to Tesla. His whole shtick is pointing out issues with their design and trying to demonstrate that he knows how to save them lots of money.
It doesn't seem like Elon is biting however. Munro's video was about unnecessary welds, and how various shapes could have been made more cheaply. Only IF Tesla implements those changes (and probably the other changes Munro was thinking about) could they save money.
Not that I don't trust the guy, but you gotta keep in mind what pays Munro's bills. He's selling his expertise.