How to add "Supplier type" to the Payable sub-ledger sources?

We have a specific requirement to drive the Invoice price variance based on Supplier type. We use 2 natural accounts to track the IPV. One for Third Party Suppliers and the other for Intercompany suppliers. When I try to use the "Supplier type" from Receipt Accounting it is giving an error " The source or User defined formula Supplier Type used in the condition of account rule isn't assigned to event class invoices.(XLA-871148) You must remove the source from the Account rule conditions, or select a different account rule for assignment to the Journal entry line.

We need some help on adding the "Supplier Type" to the Payable Sources, so that can be used in the rule condition.