Cannot add disk to cluster

I have used the SAN (HP P4000) software to create a snapshot of a database volume on one server and am attempting to use the snapshot as a disk on another server, a Windows 2012, SQL Server 2012 Enterprise failover cluster. I connect the new disk to the cluster with iscsi, bring it online, clear the readonly, hidden & shadowcopy flags but when I try to add it to the cluster available storage it does not appear in the list of disks that can be added.

The SAN snapshot process uses VSS to quiesce the databases and if I go through the same process but turn off the option to use VSS when creating the snapshot then everything works just fine. However, turning off VSS is not an option going forward for obvious reasons.

It would appear that VSS is doing something to the volume that clustering does not like but after hours of trial and error I cannot find any way to make the volume acceptable to the cluster. Has anyone found a workaround for this?

Note: I originally posted this on "SQL Server High Availability and Disaster Recovery" but got no answer.