Correct me if I'm wrong, but:
In all other instances, you can opt to cheat down assuming no on the attack flip. Shooting into melee, hitting your own model on an unmodified flip, you flip a 13, cheat it down with a 3 from your hand so you (potentially) miss or at least do min damage. It costs a control card, but it would likely cause you to miss assuming the Df flip (+1) doesn't totally tank.
Also, you need not declare the trigger. They're always optional, I believe.