@DustinB I think I expressed myself poorly; the iSCSI SR creation test does not remove the gfs2 check and does not allow it to be created as LVM.
In LVMoISCSI.cs if you set:
var performSecondProbe = Helpers.KolkataOrGreater(Connection) && !Helpers.FeatureForbidden(Connection, Host.RestrictCorosync);
The SR can be created.