Signal Filter Shunt to GND or Virtual GND
I believe option 2 is the better one.

Reason being transients being driven out on U2B have a shorter signal path to the ground of the device. If you go with option 1, the transient current need to make their way though the virtual rail driver to ground instead. Obviously a longer path through active devices.

I am however a little surprised there are no capacitors on your virtual ground connecting to the other rails. Various examples on line show some pretty large caps there/