Here you need to reference the Module "employee Drivers by Role" to get their bonus, benefits, etc. based on each of the employees' role. I am not sure how else to say it without giving out the actual answer.
It's great that you have spent some time on this issue. I will try to guide you without giving the answer directly.
What is important to note is that EMP02 Employee Expenses module is dimensioned by a subset of Employees List and your source module(from where you are trying to pull data) EMP03 Employee Drivers by Role is dimensioned by E1 Departments and Role.
Now ask yourself, for an Employee say, Mickey; how do you know which value to pull in? Since your data in the source module is present basis departments and role, do you know these for Mickey? IF you know these, then you can tell Anaplan to pull in data for that role and department.