1998 ML & Green Fog Light Indicator

I have a 1998 ML and the dealer activated the internal fog lights a couple of months ago, but can't get the green light indicator in the dash to work. I've had the car back 2 times with information from the ML forums (ie: reference MB Net message #00138 and all that goes with it). They stand fast that "it's not possible for this model year". I don't know if they're not reading the information (not really trying) or if they actually tried and it's not possible on a '98. My next step is to contact the 'regional rep', but before that I thought I'd try here for feedback and confirmation that 00138 applies to a '98.