iExpense - Responsibility to setup vacation rules

Hello
Here is my requirement.

We need to create a responsibility for certain admin users to setup Vacation rules and transfer Expense claims
So, I created a responsbility similar to the Workflow Administrator except that I only kept the Vacation Rules and Notification Search (To search and transfer expense claims).
Now, I could grant this responsibility to any user, but it will not work if that user does not have Workflow Administrator Responsibility which will nullify my requirement.

One way is to go to  Administrator Workflow » Administration » Select the responsibility created. But then, it causes issue with Purchasing and other Workflows.