If you need a replacement supply, the cigarette lighter is ignition controlled. It's a mistake! It will probably work, if the fuse is the right size to take both currents, but it will annoy you.
I used an ignition controlled power source for my digital radio aerial to save a lot of wiring. It means that you will lose the extra amp when you turn off the ignition, but the rest will carry on working until you remove the key. So if you are parked and sitting in the car, listening to the radio while SWMBO is off shopping, you have to have the ignition on fully.
I would find a permanent supply and stick an in-line fuse in it. MAybe do this rather than play with the loom. Who knows what else will fall apart when you fiddle!!
I was thinking that maybe this problem has happened before. The 1999 car has 5 wires in the crimp. The later cars only have four, with some of the wires splitting further along at connector H33-1. Is 5 too many?