Best practice question for compliance: do sysadmins get approval before setting up vacation rules?

We currently have a small group of sysadmins who can assign vacation rules if the employee forgets to before they leave.  They currently take any request (ex:  my boss left for vacation and didn't set up a vacation rule, can you please assign one to XXXX to I can resubmit my expense report).  We have several workflows (iExp, procurement, AP) where poeple are approving amounts because they are designated approvers in the company and have level of authorities assigned to them.  Compliance is asking whether the sysadmins should be responsible for validating that Mr XXXX is really the replacement sof