Addition of DLC vehicle to dispatch.meta causes a load of weird problems

ComradeCheekiBreeki

I was trying to add the RCV to dispatch.meta, and my process went as such:

Added new vehicle type called SWAT_RCV
The vehicle model is riot2, the id of the RCV
Added S_M_Y_Swat_01 as the ped model
Added SWAT_RCV to DT_SwatAutomobile on wanted level 4 and 5

After this, some very strange things appeared
First, after a while the fib2 cars stop spawning and only RCVs spawn
When RCVs spawn, they spawn with no emergency lights on and a fake driver (invisible, can't be shot out) that drives around like he's a normal ped, oblivious to the firefight going on next to him
I then tried replacing the vehicles.meta in dlcchristmas2017 (which is the vehicles.meta with the rcv in it) and added S_M_Y_Swat_01 as a driver and the FLAG_LAW_ENFORCEMENT to the flags section. Nothing changed.

I'm really confused. Not even mad or frustrated, just confused. Does anyone have any idea why this happens or a solution?

// edit ReN : moved