I gave up on trying to use the factory switch.
The factory switch is a momentary switch that signals the BSM to turn the fog lamps on and off. The BSM then triggers the indicator on the fog lamp switch when they are on, to illuminate the icon on the switch.
I installed the switch, and checked with a meter at the fog lamp relay under the hood, no go. I guess it needed to have the as built data in the BSM for fog lamps added. This is on a '06 1SV sedan, other trim levels could be different.
I actually ordered the fog lamps from Pontiac Parts people out of WA, and they were cheap. I also got the factory lower valance, so I did not have to worry about doing a bad job on cutting them ( that is me ).
Take a look at the new ones from the online parts place before ordering a new set, you might be shocked at the price delta.