Seems from previous posts that this A/C was configured for 2+8.
It's not a matter of W&B, but of everyone having:
- A seat
- A belt
- An O2 mask (remember this babe climbs up to 30k)
Someone already took the time to post the pertinent FAR.
14 on board
: if the diversion was due to something having gone wrong that's probably the very reason why the pilot did not declare (he did not want to meet a reception committee
)