That's likely it, because VTL executes at the person level there needs to be a link.
Is it possible to add a Link Field after the Custom Object is published? I assume I would need to repopulate after I create the new link field, but I'm wondering if it is possible.
Also, if I make the Link Field (email) can I have multiple records in the custom object with the same email? That's what it's for correct? Then I can reference it up to 10 records from VS?