Hmm...not sure if you're in Canada or China from your profile but here in the USA we have the Moss-Magnusson (sp.) Act which prevents stuff like this. A dealer here would have to show that something you did caused a problem and even then they can only void those sub-systems from warranty coverage.
Don't know if you have something similar in Canada (and I'm guessing not in China.) Best thing to do in this case is probably to put your original bulbs back in and go to another dealer.