No, not a 3300, although I do have 3300s that are already part of this same PDG along with other 2Ks. I have users that have moved to a remote PBX ("site Z" - not Mitel) that are connected back to a 2K ("site A") which is part of a cluster, that needed to keep their ext's. Site Z gets all of it's trunking from the Mitel network, and the users still needed to be part of the dialing plan on the Mitel network to route their DIDs to them, and to allow ext to ext dialing.
At this point I have entered Site Z's exts as ARS entries on Site A. Since all PBX's in the cluster need to know about all ext's in order to dial them, I added Site Z's ext's into Ops Man, with a home element of Site A, and everything works as far as routing is concerned (Site Z's exts just don't appear in Site A's tel dir).
SO...rather than create a separate ARS entry for each ext (they aren't in a range) if I could add this site as a cluster element in each Mitel PBX (along with correct ARS)- and add into Ops Man Network Element Editor as a "non-SX2000 PDG Member" it makes sense that it COULD work. Then I should be able to select it as a home element in the Ops Man tel dir for ext's that have moved to Site Z,and calls should route without individual ARS entries. I don't think deltas are created when cluster elements are added that aren't local elements.
Does this sound like it would work?