If he honestly wants to buy it which given the hoops he's jumping through seems to be the case then it's not 'manipulation' at all. Every move Elon makes is going to change the price. I think we all know he's not 'in it for the money' so it'd be pretty hard to make the case for manipulation. He really wants it. And if everyone else thinks Twitter would be better off with Elon as owner the stock goes up. And if he gives up trying, the stock goes down. That's not manipulation, that's sentiment.