RGB Combine tool for splitting OSC channels?

Hello : I am wondering if I can use the RGB combine (or any other tool in APP) to split out LRGB channels from an OSC (One Shot Color) image out of a DSLR. I use a narrowband filter with 2 bandpasses. One is for deep red Hydrogen Alpha (HA) and the other is  wider bandpass in blue/green to capture both H-Beta and 2 lines of OIII.

Many times, the red HA is very dominant and then image turns out dominated by red. I was wondering about perhaps splitting out the blue/green channels and enhancing them and then recombining them (at the linear stage). Is that doable with any of the tools in APP, like the RGB combine? I have tried, but not had much success in doing so. If it is possible, I would like to know the whole process flow from a calibrated, integrated linear OSC image to a recombined image with enhanced blue/green channels. If needed, I can post a link to one of my recent integrated NB images taken with the DSLR/dual band filter combo. Thanks for any pointers you can give ..... Anil