Compare invoices with orders, flag changed purchases. Every one is ready to run, and you can adjust it in plain language.
Send the old and new suppliers with the purchase request for review.
Your approver sees supplier changes after approval. Both supplier names and the request link arrive in chat.
Review the likely order and bill differences in team chat.
Your purchasing reviewer sees a likely order and its differences in team chat, or a clear reason the bill needs a closer look.