Get Cost Centre from runtime - WS20000050 Step 372

I am using Workflow WS20000050 for approval of travel expenses

When i attach the standard rule to step 372 it works fine

I have created a Custom rule and want to attach to Step 372

I need Cost Centre data for processing and finding out the agent

How can i get the Cost Centre data (entered through PR05 TCode)

I see that the standard function module uses these macros

  swc_get_element ac_container 'ORG_OBJECT' org_object.
  swc_get_element ac_container 'OTYPE' org_type.
  swc_get_element ac_container 'OBJID' org_id.

I am not able to identify the parameter for Cost Centre. It should be a table because one claim can have more than one cost centres assigned to it. it is stored in table PTRV_SCOS