Costing SLA source can use to differentiate from and To cost org

We have two types of cost organization, Operation and Service having different Inv orgs assigned to each other. Both cost org share parts to each other via transfer order.

Current Design - Business asked us to map Interog Payables account same as Interorg Receivables account only in case when transaction happen between Ops to Service cost org or Service to Ops cost org.

Issue - We created a mapping set with Source as From Inventory Org code and assigned to Trade Receipt Accrual event for Interorg Payable accounting line type. Now along with above scenario (Ops to Services) this rule also triggers when a Transfer order get's created within same Cost org and wrong account code get's triggered which is not expected.