FamilyInstance - Host ID missing

I have placed FamilyInstance (entourage, parking) I’m trying to collect the host from.
The read-only parameter Host returns the correct string for the host. But the HostId parameter is missing.
The Host and Host Face properties are null, but the element is clearly hosted.
Any ideas how to return the host?


Hummm.
Seems those properties are hidden unless the family is work plane based. Even though it clearly is hosted and moves with the host.