Thanks for the response.
This seems to be leaving the 'DRSGroup' and 'GroupType' fields blank. I have verified that the few servers I've tried are in a VM DRS Group. Any further thoughts?
Get-VM VM |
Select Name,@{N='DRSGroup';E={$script:group = Get-DrsClusterGroup -VM $_; $script:group.Name}},
@{N='GroupType';E={$script:group.GroupType}}
Name DRSGroup GroupType
---- -------- ---------
VM