This error is typical of results seen when a user doesn’t have database level access to one or more tables or views needed by the query.  You mentioned that you’re trying to create permission set(s) for the user.  This would be exactly the cause (i.e. lack of needed permission) for this error and granting of the needed access is exactly what should resolve the problem.  If you were to find a person with background in this functional area of Time Management within Human Resources they’ll likely be able to help you determine which objects, projections, etc, would be needed for access to this screen and its underlying database objects.  Once that’s done the “table or view does not exist” result will be resolved.