I'm not sure I agree. The 59 has ailerons hinged at the leading edge while the 18 has a hinge point further back. The video shows ailerons with a tubular spar which is indicative of an off-set hinge point.
Would love to see an IPC for either airplane to be sure.
Well, the radiator could be the decisive clue. The 18 has an annular cowl where I assumed a radiator could live (the Pitts I had owned has a similar design). However, just found a drawing of the 18 engine installation and the radiator is right above the fuselage in the wing support structure.