Purchase Requsition WF change agent assignment

We have a Purchase Requsition Workflow where the agent assignment is made as WF-initator.

The problem is when WF-BATCH has created a Purchase Req he gets the workitems of decision. We need to change this so it goes to some real agents.

Where not sure who we should assigned the workitem to, since EBAN-ERNAM is WF-batch.

And also how to go with this agent change, should we make a rule inside agent assignment for the tasks or perhaps a method?

Helpfull answers will be rewarded.