Well, the way it works is that the flaregun, the detonator, and the scorch shot are all replaced with a flaregun that works like a detonator. It's confusing, but it's a carry over from the VSH mod.
Additionally, on certain maps (namely wooden and hotdesert), we replace the detonator and the scorch shot with a normal flaregun, since otherwise they can be used to activate some traps.
In the future, we may just filter button presses so only hale can press them, so we can give players normal pyro weapons.