I have not found a way to apply a random pan and zoom to more than one slide either. The method seems to be to drag the random pan&zoom to all applicable slides.
If you want to apply one particular pan&zoom to all slides it is a bit more simple:
Apply the desired pan&zoom to one slide, and then copy the keyframes of that slide and paste them to all other slides.
I suggest you send CL a suggestion to make the apply to all function available again, maybe it helps.