Tesla’s current valuation is pretty much thanks to him. His personality meme stocked the company to a valuation that made no sense.
And nobody has a larger interest in Tesla's valuation them Musk himself, the largest shareholder.
He can't walk and any threats to that effect are theatrics. Shareholders would be idiots to re-approve the $55bn.
Put another way, which company is more likely to exist in 10 years: Microsoft or Tesla?