Well, I think I can make out a timing chain to the right, that connects both cranksets. Which in turn means there's got to be some double-hub-shenanigans going on on the rear, otherwise the whole thing won't move.
Yeah timing chain outside the triple chainrings up front but cranks are definitely out of sync. Could just be poor setup.
Don’t know about the double hub, looks like a normal hub to me with the stoker cranks bolted on the outside of the dropouts but don’t know how that’d work.
Looking at the photo I don’t know that the pilot and stoker cranks are synced.
I’d thought the stoker cranks would be synced to the pilot cranks and then they would drive the rear wheel but who knows.
Also looks like the Q factor might be huge.