To be honest I don’t remember anything about multiwii as I have not touched it for a good couple of years as it is no longer active. It might run sbus, but frsky sbus is actually inverted so even less likely. Sorry I can’t be much help.
This would be the best place to find the answer:
But my suggestion is to rather get a newer flight controller that runs the latest firmware like betaflight or iNav. The link below discusses the various projects if you are interested