They expect locked up shares to hit the market in August and tank the price

They also see one of the most ridiculously overvalued stocks of all time and want to collect easy money.

Only if the market is rational

That could happen, but should also consider that it's often the case with lockups release that they do not inflict much change on the stock price, but only if there's already enough trading volume on the stock due to other market conditions.

you clearly over-analyze the problems ! The right question should be answered is: after the investor who participated in the spcx pre-sale, receive the lockup shares, what will they do ? And what makes them do that ? Under which conditions ?