The MMs cover very quickly. They know how quickly pumps can die. Most last for no more than three days, with volume falling off on the last. You know, MMs aren't STUPID. They know a lot more about how stocks trade than we do, because that's their job.
Too often it may be actually be a short selling scam disguised as a "pump".
Sheesh. That's just ridiculous. Promotions are often paid for by large shareholders who want to sell, and need heavy volume to do that, but it has nothing to do with the shortselling you seem to be obsessed by.
Isn't it ironic that the "panic" immediately follows the pump much too often?
Not at all. What goes up must come down, when there's no substance to the run. The momo guys rush for the exits, and it's all over.