So the red module is lower power, but is it lower voltage, lower current, or both? And you're trying to use a single driver for all three?
If all three LEDs have the same current rating (or at least all have a current rating above what you need) then you could use a single constant current driver and then switch which LEDs are connected to it. You'd ideally want to turn the driver off before switch loads, though.
You could probably overdrive the red module and PWM, provided you're not going crazy overboard. Does the datasheet give a peak current rating? Some LED drivers allow the output current to be externally programmed, so that could be an option as well.
Using three separate drivers would bring some nice feature advantages, like the ability to crossfade from one color to another rather than just making a hard cut. You could even sort of do a tunable color temp white--only 'sort of' in this case because you won't be able to mix the output of two separate COBs very well.