You're making assumptions about them having two engines. I also wondered about that but in speculative retrospect it appears they only had one engine running at the worst possible time. The NTSB doesn't care about speculation, they will dig deep to find the factual evidence. You're just going to have to wait, it's called delayed gratification, something folks nowadays somehow find baffling. I can remember ordering stuff from magazines that would take 6-8 weeks and were C.O.D. My first balsa airplane model was built based on this method of production. It was a glider and it flew, but it didn't fly well. I was probably 10, so my aeronautic knowledge was lacking. I need more experience regarding weight/balance and the construction of flying contraptions, not to mention I'd started riding motorcycles and that seemed way more exciting.