Create a custom role for HCM API with Read Only access to Worker data restricted to one Legal entity

I have a requirements to setup a role for API use with read only access to worker API. The Role also needs to be limited to one legal entity or an employee.

I have created a job role with the following functional security policies and the data security policies and the worker API (/hcmRestApi/resources/11.13.18.05/workers) returns the data. As soon as I have applied a "Select by Key" restriction on the data source, the worker API stops returning data any data. (Note I have run "Retrieve Latest LDAP Changes" each time)

I have tried applying already existing and working data security policies on this Job role and was not successful.