Nobody has the key to cryptocurency or bitcoin to be more specific to just shut it down if that's what you meant by Satoshi having the key to bitcoin. If he was to resurface today, I doubt if he'll have much influence on the market unless he was to cause fud by dumping those 1million coin he mined early in the days, which will send a wrong signal of the founder of the biggest innovation in the 21 century dumping his plans.
Bitcoin is a community project that has constantly been improved by the community. It's the closest to decentralization we can ever get in the industry. In regards to the recent news from Tesla, I just believe it's an attempt to manipulate the market and nothing else.
I won't be surprised if we find out the government are behind this, those guys are capable of doing anything just to keep staying or having power over the mass which bitcoin is a threat in the eyes.