Haha sorry, forgot to add a Amplifier for a car speakerBeats me, since I have no idea what amplifier you are referring to.
The remote wire is a turn on signal from the stereo head unit.
My question is, why do you need a kill switch? The remote wire turns on and off through the head so why would you need another switch.
Does the head unit have the remote wire coming out of it? Blue or blue with white trace? If it does, can you check to see if it is working when the unit is on or off?