orbi app only showing 1 of 2 separate routers

Orbi app doesn't support Orbi Pro. You'll need the Insight app for Orbi Pro.

Netgear has set up a community forum specifically for the Orbi Pro products. Most of the people who watch that forum are more likely to have experience with Orbi Pro and know how to work it better than those of us who follow this forum. Might be more likely to find someone who has a solution if the question is posted there:
https://community.netgear.com/t5/Orbi-Pro-WiFi-for-Small-Business/bd-p/en-business-pro-wifi

Please use this link to the main forum product list to review and choose where to make your posts. 
https://community.netgear.com/t5/NETGEAR-Forum/ct-p/en-netgear

Thank you.