Please read the following BASIC Investopedia article before spreading manipulation theories on why you can't get filled... it is YOUR broker, not the MMs...
A Broker's Options A common misconception among investors is that an online account connects the investor directly to the securities markets. This is not the case. When an investor places a trade, whether online or over the phone, the order goes to a broker. The broker then looks at the size and availability of the order to decide which path is the best way for it to be executed. A broker can attempt to fill your order in a number of ways: