Zendesk Macros: organization placeholder in the Subject is not resolving for End User requesters

Hello,

We are using the Zendesk API to apply a macro that sets the ticket subject to "Attention Requested: {{ticket.organization.name}}..."

This behavior has worked correctly as expected for the past few months, but around the beginning of August we have noticed that the placeholder is not resolving for any requesters that are of the "End User" type. The placeholder continues to correctly resolve for "Staff Member" user types, however. 

For example, here is a list of tickets with an End User requester created by the API using macros. The tickets created on April 7th resolved the {{ticket.organization.name}} placeholder correctly, whereas the ticket created this morning did not resolve the placeholder value, even though the requester's organization has not changed since. 

This behavior has been consistent (i.e. the organization placeholder only resolves for Staff Member requesters, but not for End User requesters) since August. Before then, the organization placeholder was resolving for users of all types. 

Are there any configuration/setting changes that may resolve this type of behavior?

Thanks!