Ya'shenn would be able to know what's going on, if she concentrates, but she's got problems of her own, too.
For Azreal: Mechanics-wise what we've got by my calculations from 3 rounds of slugfest is Ar'dru down to 10 hp, the Yuan-ti down to 9 hp. Yuan-ti moves first. Now, I can write up a suitably epic battle, I suppose, or you (or another player) can try it. Ar'dru still has to make a DC 17 fort save or be poisoned, but only once (the serpent had poisoned the blade or got in a bite).
For Weishan: After consideration, as a portation specialist, Na'rai can use d-door ability as a move=action, so can 'port and attack in 1 rd.
Ya'shenn's mindlink with K'tch may still be active... if he would like the rest of the party to help, or anything...
BoGr Guide to Missile Combat:
1) Equip a bow or crossbow.
2) Roll a natural 1 on d20.
3) ?????
4) Profit!