Is there a way to place requisitions “On Hold”? In normal cases, service teams would stop working on the requisition until they get another approval. However, this will affect SLAs and escalation emails will also be kicked out.
During service delivery, create an Ad-Hoc task and be sure to check the Pause current task until this ad-hoc task completes checkbox. This will not change the SLA, nothing can do that, but it will pause the clock so that the system does not send late notifications.