AEM 6.1 Subform - how do I update without touching parent forms?

Previous users created subforms for specific images then added those subforms to a bunch of application forms.  Now I need to update those images but updating only the subform does not seem to have worked.  Is odd too because if I bring up a parent form in AEM Workbench, the subform's image is changed; when I flatten the form or run a test against the library, it is not.  I've synchronized and deployed both the subform's application is in and parent form applications without the desired result.

New to AEM and I don't know what I don't know.   Anything may help.  Thank you!