You are misreading the wall and what it represents. Simply it is a way for the entity that put up the wall to buy at below the wall price. If they wanted to sell they would sell at market price and be done with it(while creating this panic you are worried about). This really isn't rocket science. The only walls we should be worried about are buy walls because they denote a major sell off is imminent.
Happens every...single...time.
Huge sell walls are great. The whale is manipulating up.