EHSM Security access_ to log Incident for people outside their own org

Our customer for EHSM is not typical in how they use the EHSM , they want the EHSM users (Supervisors for all orgs) to be able to log an incident for anyone outiside their own organization unit.

Ex: Bus driver has an Employee from HR on the bus, and the Employee slips on the steps. The Supervisor in not in the same org unit, but would want to complete a EHSM Incident record in SAP for the employee that hurt themselves. So they need to be able to select them as an person from SAP HR outside their own org.　

Therefore we need to open up the EHSM security to allow this to happen, but still limit the view on the HR data for that person. In many cases the Supervisor would have PA20 Display Master Data access to view the employees that are direct reports. But we do not want them to be able to see the people outside. Any thoughts