No to the EMP and other grenades, yes to the vehicle mounted turrets, though ramming your vehicle intentionally into enemies is against the rules. And before its brought up, traps are Ok, though by your Second auto turret, you probably won’t need to worry about it.
There are no win conditions, this is just a new was to play the game as a challenge. If you want a challenge, then make up some arbitrary goal like say… Wipe out a fungal bloom using only manhacks and turrets, and no interaction beyond deploying them. Watch as your automated minions wipe out mushroom things from the comfort of your own mobile battle death fortress of doom and rainbows.
As for the 9mm, a single turret can easily wipe out the better part of a fungal patrol.