Procure to Pay Lifecycle Tracking

We have situation where buyers have SLA to created Purchase orders from approved purchase requisitions, but occasionally few variables come in the flow e.g.buyers waiting on some addition docs from vendor, renagotiating the contract, waiting on legal approval etc and SLA is not met. In such cases, the buyers don't create the PO and maintain offline spread sheet with live status of their requisition pool, but the requesters have no visibility into why the buyer is not creating the PO for their requisitions, unless buyers provide them status via email or some thing every time or requester calls buyer to