Curious to see what came of your issue. Did they replace your vehicle due to water damage? I, too, had water come in from the sunroof on my 2021 Tahoe. Started 2 mos ago and water poured in through the roof console (where sunroof controls are), then through the rear passenger dome lights. Noticed water streaks on the front door jams. Could hear water sloshing above cabin. Put in shop for 3-4 weeks where the removed headliner, had to replace the sunroof and ultimately the motor in the sunroof cover after it was damaged by water. Morning after getting it back, when I cranked it, I had no electronics-no backup camera, no touch screen, no radio, no driver command center (in dash behind steering wheel)--all blank-non operational. Took it back but with holidays, no one was available to determine what they were going to do. Picked it back up & have had the electronic failure twice since. I fear it will never end--who knows how much water went into the dash or could have affected the control panels/computers. I, too, have asked for GM to replace it. Back in shop now & they are working toward that but GM doing every conceivable test, diagnosis to keep from having to replace. Thankfully, the dealership owner is involved and advocating on my behalf. What a mess.
Did you get anywhere with this or a solution to the water leak? We just bought our 2021 and our drivers side floor board is completely soaked. Sat at dealership for 9 days and they couldn't find anything wrong so they sent us on our way.