Hi David, I’m Louie. Sorry you had to wait awhile but I’ll do my best to help.Initially, bear with us; re-confirm and post back with the complete model number of the mixer.
Appreciate the additional information David.
Have you considered / tried connecting the Roland TRI-Capture's OUTPUT jacks to the Yamaha MG10XU's LINE input jacks 7/8 ?
Do you have a pair of RCA to TS cable similar to the cable shown HERE ?
...or 9/10 ?
...using a TS-to-TS cable something like the cable pair HERE ?
Improve audio output; yes in terms of dB gain. There would be more headroom; i.e. the resulting system is more efficient as it has more handling capacity thus can even exceed designated nominal level.