Why not listen to the dealer? The keys transponder is INSIDE each key so they're right. Any new key then needs software downloaded from the dealers Vadis PC in order to work OR it will not start the car. The same PC can see the keys transponder thus test the system so they do have ways to know that w/o guessing.
You'll waste ALOT of time trying to figure it out and try bypassing their system BUT do realize that there is no simple way around it as it's been created to stop professional theives with expensive theft devices from stealing cars like yours. If it was simple, the theives wouldn't have problems either.
You'ld be best to just let the dealer fix the problem.