Multiple Wires Under a Set Screw Neutral Bar

[steelersman]

There supposed to be a separate neutral bus and a ground bus.

Yes if it's a sub-panel, but in the OP's case it is a main panel and therefore it is ok to have EGC's and neutrals on same bar, just not same terminal.

 

[tkb]

If you were to use a twin wire ferule would it count as one wire or two?