Multiple led matrix

Hey guys, 

I've built a dash box that has 2 led matrix units in it. 1x MAX7219 dot led matrix and 1x WS2812B rgb matrix. 

I have the Max7219 set-up for gear indicator and the rgb unit for flags and pit limiter indicator. ( I know I can do both these on just the one rgb board but I didn't want my gear indicator to disappear everything a flag came up)

Now at the moment I can't get these to work off one board as it just defaults to everything showing up on the rgb board as well as the dot matrix. 

Is this a simhub limitation or is there a way to control both LEDs separately on one board. 

Thanks