Yes I agree. Basically the dealer wants maximum reimbursement from the manufacturer so you don't have to pay as much so earn your business.
Just bare in mind if they have a long line of $100 oil changes in the queue, there isn't much incentive to tie up their techs to perform a repair that...
I also think window should be first, BUT i can see why the seatbelt is important. When the water rushed in, you'll likely panic and can't get seatbelt off, especially when you have precious cargo in the backseat.