The Create/Change/Lock vendor master records from HR master records screen appears.

You can also specify further selection criteria using the Further selections function.

The requirements for the reference vendor master record can be found in field help for the Vendor field.
Since you must confirm every information message documented for a personnel number manually in test run mode, it is better to perform the test run for only a small number of personnel numbers.
Result
The program has created a work file. If relevant, the system has also transformed the work file into a batch input session that you can process further in Financial Accounting