JD4 I think you can put in each channel from your mixer into the sound cues mixer. Then that mixer will combine each into a mono channel or into stereo depending what you are after. I not sure exactly what your after but a mixer mixes sounds into a mono channel or stereo channels. The left or white rca plug is always the mono channel. When dealing with a mixer setup. It should mix all 32 edited sounds into 1 mono channel or into 2 stereo channels depending on what you are making in the mixer. So you should not need to input 32 mono channels, that mixer should mix all 32 and put into 1 channel. If that phase of each mixing INPUT CHANNEL is not the same(as in + or -) you can cancel each others audio amplitude of the 2 channels you are trying to mix. So be careful when mixing sound. That your phase is the same where its + or -. Each channels time delay should all be set the same on the mixer so that you do not get distorted signals from those channel.
Example what i am mean by time delay distortion is, lets say we are both at the back of a car and we will both push it forward at the same time but if the time delay is not the same it would be like you pushing then me pushing because we are off and we want us to both push at the same time so make sure your time delay matches, so we both push at the same time so you do not get time distortion. Hope this all helps when mixing.