You don't need PC for Reblochon at all. It starts with geo growth, then washed with brine (which may have geo, yeast and b.linen in it), then you let go when the rind becomes orange and it covers with a secondary late bloom of geo which looks like a white powder. That's sometimes mistaken for PC but it's just geo, no PC.
In Camembert Geo is minor and PC is more important. The geo just creates the initial rind and deacidifies the surface for the PC to grow. It then needs to be controlled. It also has effects on the flavor and texture as well as rind appearance. Use less of it to get a less agressive and thinner growth.
In St. Marcellin the geo is very important and pc has a minor growth. It is a tiny thin cheese that ripens very quickly with geo and it needs to be gooey.