Exporting multichannel with Stereo, Surround, and Stems

Hello!  Trying to export a ProRes 422HQ deliverable, and they want the multichannel audio to be set up like this:
Stereo L/R

Surround 5.1

M&E Stem L/R

DX Stem L/R

FX Stem L/R

MX Stem L/R

The audio files were sent to us from a trust sound studio, and the specs are all correct.  My sequence looks exactly like what they're asking for.  I used the Audio Track Mixer panel to make sure the patching was sending the right audio to the right channels, and during the export, I made sure the audio delivery was showing proper mapping as well.  After all of that, when I look at the audio of my export, It shows me 8 stereo tracks, and fails the client's QC process, because the second track shows up as stereo.

My edit rig does not have a 5.1 setup, and I'm wondering if that's preventing the export from arranging the audio the way I'm expecting it, even though the 5.1 file I got from the sound studio is solid.  Or is there some other function I'm unaware of that I need to address as well?  I'm using 15.4.0 currently.