It is actually the opposite. Incitement of a insurrection would have been lengthy, subject to appeals, Freedom of Speech. The charges he was charged with are easy to prove. If you can't prove these then you will never get the others. These charges turn over more dominios to charge others as well, once one falls the others will as well. Reason the others have not indicted as of yet so the thought would be "you are either going to be a co conspirator or a criminal". Show half your hand, and hold the others off to the side. The simple charges are for beating the clock, setting doubts, and slowly screwing the process in a short period of time to beat the Calendar.