[ovirt-users] Do distinct export domains share a name space? Can't export a VM, because it already exists in an unattached export domain...

After OVA export/import was a) recommended against b) not working with the current 4.3 on CentOS 7, I am trying to make sure I keep working copies of critical VMs before I test if the OVA export now works properly, with the Redhat fix from 4.4. applied to 4.3. Long story short, I have an export domain "export", primarily attached to a 3 node HCI gluster-cluster and another domain "exportMono", primarily attached to a single node HCI gluster-cluster. Yes I use an export domain for backup, because, ...well there is no easy and working alternative out of the box, or did I overlook something? But of course, I also use an export domain for shipping between farms, so evidently I swap export domains like good old PDP-11 disk cartridges.... or at least I'd like to. I started by exporting VM "tdc" from the 1nHCI to exportMono, reattached that to 3nHCI for am import. Import worked everything fine, transfer succeed. So I detach exportMono, which belongs to the 1nHCI cluster. Next I do the OVA export on 1nHCI, but I need to get the working and reconfigured VM "tdc" out of the way on 3nHCI, so I dump it into the "export" export domain belonging to 3nHCI, because I understand I can't run two copies of the same VM on a single cluster. Turns out I can' export it, because even if the export domain is now a different one and definitely doesn't contain "tdc" at all, oVirt complains that the volume ID that belongs to "tdc" already exists in the export domain.... So what's the theory here behind export domains? And what's the state of their support in oVirt 4.4? I understand that distinct farms can't share an export domain, because they have no way of coordinating properly. Of course I tried to use one single NFS mount for both farms but the second farm properly detected the presense of another and required a distinct path. But from the evidence before me, oVirt doesn't support or like the existance of more than one export domain, either: Something that deserves a note or explanation. I understand they are deprecated in 4.3 already, but since they are also the only way to manage valuable VM images moving around, that currently works with the GUI on oVirt 4.3 it would be nice to have these questions answered.