Have two nodes point to the same annotation element

This is a customer reported issue:

The customer has multiple BPMN 2.0 tools and all looking for interoperability across platforms. When a annotation is referred by two elements on a BPMN 2.0 diagram, it cant be opened and fixed in RHPAM. This will be have to be fixed in another modeling tool before opening it up on RHPAM.

Customer Feedback: Having two tasks pointing to a single annotation causes validation errors, this is a minor issue but will become a problem as the author may change this and it will unexpectedly create an import issue into RHPAM. Example here