Hadi77KSA Thanks for the reply! I will try getFunction and we'll see if it works 
I do want to ask, what's the difference between scripts/sp/zom and raw/scripts/sp?
when I put any scripts in the scripts/sp/zom folder they just don't execute at all. They only work in raw/scripts/sp.
inside scripts/sp/zom there is a zm_spawn_fix.gsc file with a comment saying
// this is intentionally blank as we moved the location of the file
The populated file is in raw/scripts/sp , so I assumed scripts/sp/zom was depreciated?
EDIT:
fn = getFunction("maps/_zombiemode_powerups", "specific_powerup_drop");
This worked thank you. I am still inside raw/scripts though.