So quick update - back from dealer
a) passenger airbag replaced under warranty.
b) electronic child safety in the cluster- some windows not working when it happens. BTW It happened again once last week and kids were seated at the back. So it happens only when kids are in the car.
Little upset cause dealer did investigate a little and since they were not able so see fault code (even if it happened again a week ago) and were not able to replicate the fault in the shop. So they look at wiring and it looks ok but I doubt they did lot of researches. However they opened a case with VW canada and they spoke about that issue with the "VW rep". Rep says it happened to some 2018 GTIs (I'm a 2018 GSW) so I confirm we are not alone. Dealer said their best technician for eletrical stuff is off for vacations and it would be better to wait his return to go further in this. ANd that VW of Canada accepted to pay them.
However, service manager told me VW rep said that they found in some cases that the problem was causes by the driver's cell phone, She said it's important to put the car in the center console while driving. Not on seats or in the door compartment. Cause some phones generate a lot of "magnetic waves" and can confuse some modules on the car. Ok.... honestly my BS radar rang at that moment. But after some reflection, sometimes I put my cell phone on seat or in my door storage...
So in the end, we booked a new appointment for early september. And she said, if it happens again, take pictures of message in the cluster and take notes of which windows aren't working, who and where are seated people in the car and were the phone is located at that moment.