Fascinating.
It seems to me though, that the RPMs of the wankel are too high. They need a compression ignition version of it running in the 2-3 thousand RPM range. But then they won’t get the self stratified charge effect.
Maybe with a counter-rotating prop in a duct, the higher RPMs could be effectively utilized without gear reduction...but then you are fast approaching a turbofan. Perhaps a poor-mans turbofan could consist of a turbo-compounded-wankel driving 5 blade counter rotating propellers in a duct?
As I undestand turbo's they turn heat in to motion energy. The compounding if you will, turns it into shaft power vs. back into the induction system as boost.
With poor thermal efficency, the Wankel would be a natural given the high exhaust temps. So, take those losses and turn them into motion?
Take a look at Lamar's website. He used to have a Cad 2D drawing of the concept you noted. A 3 rotor Wankel with direct-drive in a duct, turbocharged but I think this was before he was into the Turbocompounding as a poor man's jet engine if you will....