Maxi Youtube should at least work in Compatibility mode(with ads),
I read OP as saying he wants to use Orion and play videos WITH the ads. I would agree to wanting at least thiis functionality, even if potentially changing some Orion settings on Youtube.com.
EDIT: in reading above posts, I changed User Agent to iPad and it worked. Is this the best current solution?
EDIT2: using iPad user agent prevents keyboard keys (J,K,L etc) to work
EDT3: Sorry for multiple edits, selecting Agent "Edge" seems to work