Delaying laser exhaust and air assist off through custom postprocessor?

Hi all - I’m using a laser w/ OF Buildbotics controller and Vectric laser module. I’m going to trigger air assist and a smoke exhaust fan with M3 command/tool enable pin 15.

So I see Vectric PP ends like this:
image

If I want to change laser power to 1 and allow 15 seconds for cool down and more smoke exhaust, would a custom PP for laser use with this footer do the trick?
image

May well be obvious, but I’ve never played with the post processors yet. Thanks!