The AIN structure, including the in-memory structures seem identical to Titanfall 2. I mapped quite a few 'CAI_Network' related functions out and everything seems to line up. But I haven't figured the script nodes out (yet), but looking at this, it seems like they got completely stripped? TODO..
I also found where it creates nodes/links from input NavMesh, the poly structure also seems identical to Titanfall 2, but still haven't found where this extra field gets used.