At altitude the B-36 was fast enough that the F-94 was a stopgap fix so they could possibly have an escort. Of course a raid on Moscow would have been a final suicide mission. No one expected to come back. Under such a dire situation, the B-36 was not going to be the only delivery system. The F-82s were tasked to deliver a bomb at low altitude to hope to evade the radar that would have easily tracked the B-36s. In a way the B-36s could be used as decoys. From what i understand, this is the second time a rocket motor has blown. They did one test at sea and it polluted the ocean when it blew up, so they moved it on shore hoping they could contain a problem without international questions.