Ok. Let's try a small FAQ

- Both CDJs are controlling the same deck?
=> Change the MIDI channel on the CDJ according to the doc.
- Both decks are outputting to the same CDJ?
=> You need to aggregate both CDJs either using the Pioneer tool (check their website), or doing a manual aggregation in mac utility "Audio MIDI Setup".
=> In Cross audio preferences, select the aggregated device, check the routing mode is "External Mixer", check both outputs are routed.
But all these information already exist on this forum.
Let us know how it goes!