We have had several similar problems on our 2003 New Beetle TDi. We had an airbag warning light come on after we had taken it for the 60k service - the warning light came on within 5 days of the service. Local dealer diagnosed the problem as an open passenger seat belt buckle, which they replaced for $265.20. Nine days later, airbag light came on again, and the dealer diagnosed it as a failed passenger seat igniter. They replaced it for $304.02. I sent a letter to the VW Customer Care Center asking if there were similar reports of the airbag system failing on this model, or reports of 'coincidental' problems after taking their VW to this specific dealer, or if they felt that spending $762.08 on service and repairs in the space of two weeks was simply coincidental, as the local dealer stated. After 3 weeks, I received the reply "Our records indicate this vehicle is currently unaffected by any open recall campaigns. If you experience future concern, please feel free to contact us." I wish I could give you better news, but I believe you may be heading down the same path we just followed. Good luck.
Goebel