Can I route two keyboards to separate channels on a Behringer Q 32 system using a Focusrite 4i4?

I am a senior player, so go easy with me! Lol. I just recently went to both keyboards being midi. The church gives me a total of four channels so I can be stereo. I am using a Focusrite 4i4. Our Church utilizes a Behringer Q 32 system so I am using there in IEM.

My question is, am I able to send the keyboards to those separate channels at church so they can be separated and I can adjust my ears? I would like my 88 key to be on channel 15/16, and my 61 key to be on channel 17/18 so I can adjust the volume of the keyboards separately in my ears. Again, I have the 4i4 and two stereo DI boxes. Am I trying to do the impossible? I hope this all makes sense and thank you so much in advance for any help you can give me.

[Re-Titled by Moderator]