Upon further changes to my DLC.rpf, I moved the files around, assuming I may have had them in the wrong place. I'm now able to get the cars to blip a target vehicle, however, when toggling the siren on, I do not get the prompt that the vehicle has been signaled, and the target vehicle continues along its normal pathing, I'm assuming waiting for me to activate my siren. When tested against my other replacement vehicles, they perform as expected. Vehicles on road still do not react to lights/siren when activated and continue as though no emergency vehicle is present.