I have a couple of problems with your post.
Manipulate, schmanipulate. So whales can't buy or sell large amount of stocks? Not to mention only the futures part is regulated and bitcoin isn't, so what can I do, I move the BTC price? Not my fault. That isn't manipulation, just simple cause/effect.
Second, I don't believe the MtGox trustee caused the crash. Sure selling large amount of BTCs didn't help, but it was a nobrainer that 20K couldn't stay up. If you had a decent amount of BTC, you had to cash out at least some of it...
But anyway you are saying that this BTC/futures double play could be done except it might be illegal and it needs a bit more money. Maybe if the BTC part is done in more brokerages where the effect on the price is more effective. Now we are talking about manipulation...
The manipulation may have already happened through the printing of USD tether that kept pushing the price of bitcoin in December. The manipulators, however, may have been outside of the reach of the US regulators.
The situation is skewed in favor of the longs as the btc supply is limited on any of the exchanges and can be easily pushed up, as long as there is no immediate need to dump at the market.
There are a lot of bitcoin in private wallets of whales, but these guys don't need to cash out in one shot. They've probably cashed out more than enough to satisfy whatever it is they've always dreamed of. The bitcoin "Lambo" folks are not the early investors/whales.
Just speculating as I follow many of these people on twitter (and many are underground/anonymous) and they are not buying private jets or mansions or expensive jewelry and flashing them on social media like sports superstars or music moguls. They're wired differently, if you know what I mean.