The only ways I can think of to clock to an outside system is with BNC connection on the Apogee clock card or through light pipe via ADAT optical. I pulled this from a manual somewhere in regards to the BNC connectors on the DIO8 cards.
In addition, it has a BNC connector, which provides a DTRS clock output for devices
that require it. The DTRS clock is the same frequency as the word clock, but is 90 degrees out of
phase with the standard word clock.
If you can get the Red rig to sync to that... ?