I don't see an issue with this as there is more things to do in the donator zone. But you also have shops, trading post, etc at the Edgeville home location. But I guess it does no harm to have another teleport mage at ::dz. Would be a nice little small benefit, support.
As Mors said it was suggested before and denied. Mainly, because they want to keep the home area more populated rather than split players between dz and home.