In a word, 'no'. And there will be no way around it. In order to ride on the DME, you must be listed on a resort room reservation. Your group goes over the occupancy limit for a WDW room. If one of the kids had been under 3, then fine. But they aren't even close.
Besides, with your size group, even if you do squeeze into a room, someone is not going to have a room key, which means someone isn't going to be able to participate in the EMHs.
It is against board guidelines to discuss ways to get around Disney policy. Let's keep that in mind.