One time supplier

Dear AP Gurus,

Here at our client location we have a requirement of creating invoices and releasing payments for certain type of suppliers (petty).

I suggested a solution of create a supplier name 'Temp Supplier' and process all invoicing and payment related to above category of suppliers through this single supplier  'Temp Supplier', we have customized our check printing as that, if we have any value in Attribute-1 , print it as payee name, if it is null, then pick the supplier name for payee name.

It has been running quite well for last year and half... but now internal auditors questioning this solution, so... is there any document or whitepaper, available to substatiate my this solution,