No, that dealer is not wrong.  The handle can be supplied with a random
code.  In that case it does not have to be special ordered, and comes
with two keys.  Those keys will only fit the new handle.  A coded handle
can also be special ordered.  It will have a lock tumbler already coded to
 the same key code as the vehicle was built with (or any later key code
that was recorded on the vehicle data card, in case the locks were
already changed for some reason) and will come with a single valet key.
 The valet key is made first, to code per above, and the handle is then
test fitted to the key.  If you don't want the extra key, toss it.

Dealer is a doodyhead. The lock mechanism and handle are different and the
lock can be removed from the handle. JUst get a good used one (car-part.com)
and swap your lock cylinder in.