On behalf of Dan, issue solved
The error we were getting was:
"Type 'Phoenix.ORM.GSGlobal.TypedViewClasses.SubscriptionHistoryViewRow' in Assembly 'Phoenix.ORM.GSGlobal, Version=1.0.0.0, Culture=neutral, PublicKeyToken=b3db7a2830c3b794' is not marked as serializable."
So, we've acknowledged that a ViewRow doesn't serialize because it is a DataRow. As suggested by simmotech, I changed the return type to SubscriptionHistoryViewTypedView, which does serialize, then on the Business side I am able to extract the SubscriptionHistoryViewRow after deserialization.
Thanks for everyon's help!
Litho