For what it’s worth, it’s been suggested that Musk’s takeover of Tesla was opportunistic, and against the desire of Tarpenning and Eberhard.
From my research, Tarpenning was pressured into quitting, and Eberhard was fired by the board of directors for lying to the board. Since Elon was chairman of the board at the time, it’s plausible (and even hinted at) that Elon played dirty to push through this firing.
I cannot say for sure if they would have handled the company more ethically then Musk, but I am personally uncomfortable hanging them out to dry simply on what could have been.
That said, I agree that employee co-ops are a top tier business organization structure.