Unable to remove host from vCenter

We have an existing ESXi 5.5. host we're unable to remove from a vCenter server environment. When attempting to do so we get the following error:

Remove host

<<hostname>>

Cannot complete operation due to

concurrent modification by another operation

We are able to add the host back to this vCenter environment as well as add the host to other vCenter environments. Further we're able to remove the host from those other vCenter environments. I believe the culprit is a VM thats reported as being orphaned on that host. This VM only shows as orphaned on the vCenter server we're unable to remove the host from, not when the host is added to other vCenter servers. When we attempt to remove this host the vCenter server we get this error on, all of the VMs on that host are removed with the exception of the orphaned one.

Any thoughts on how to resolve this before we open a ticket with support?

Thanks!

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