From the audience perspective, it's almost impossible to tell that the high wing guy has dropped down. I've seen the same formation photo pass, but from a completely different location, and from head-on you can tell very clearly that the high wing guy isn't symmetrical. It makes it look a lot better for the airshow audience and if they were in the usual perfectly symmetrical positions, it would really look like someone was out of position.
Take a micrometer and measure the lengths of the wingtip rails... In the photo it looks like they're almost touching so they should be pretty much the exact same length. If you measure them however and the high wing guy's rail is shorter than the low wing one, then that means the high wing guy is actually farther away. The only way to get the rails lined up but still be farther away, is to have the high wing guy drop "down" and "out" from his normal position.
I've seen this effect from inside the cockpit flying in all 4 of those positions, as flight lead and wingman in 4-ship formations. It's all a matter of perspective, and some of the airshow formations rely on simple visual illusions to change the appearance of the formation.