Fathom ROV Tether connection to Fathom-X Tether Interface Board

Hey Good Evening,

We are in college. Doing a ROV project. So we ended up buying most of the electronic components individually. And now we are having trouble wiring the whole system.

The obstacle we are facing currently is, understanding tether's end wires. What are their applications? More specifically, how would I connect the tether to the fathom-X board?

We also tried researching more about schematic diagram of the the whole blueROV2. We couldn't pinpoint a single reliable source so far. from 2018 we found a discussion with the same problem. But the solution page/website no longer exists.

Any help is greatly appreciated.
Thank you.