Thanks for the responses. Dang!
I want to use the AES out to feed a TC Electronic Clarity M meter, while simultaneously using the AD to feed optical out into MTRX Studio for my mix 2bus print. (I do additional processing ITB and have other sources from my computer that I want to feed the Clarity M with, so only metering the AD input doesn't really cut it.)
The MTRX Studio only has ADAT optical, no SPDIF or AES. Which is also annoying because I originally wanted to just feed the Clarity M with optical out from the MTRX but it only supports ADAT not SPDIF optical.