Question

We have a 64s for FOH, and we are wanting to move the livestream to another room to separate the mixing.

Answer 1

Sounds like you are needing to send signals to both FOH and to a separate room for recording.  One NSB32.16 will work, you do not need two NSB boxes.  Set each console as a "stand-alone" and make the FOH console the "managing" console (for gain level and phantom power).  The recording console can use the gain-compensated streams for recording.

Make sure to setup both consoles as stand-alone.