TAM/CG: Offer Accepted Last Updated By field is blank

On the Manage Applicant page of PS HCM 9.2 when an offer is extended to a candidate and the candidate accepts that offer, the disposition updates to "offer accepted" with a given date/time stamp but it does not indicate that the offer was accepted BY the applicant in the "last updated by" column. Further, in some cases, when the applicant accepts the offer through the applicant portal, the "last updated by" column indicates the recruiter's name, even though the recruiter did not accept the offer on behalf of the applicant. 

How are others locating the proper acceptance for audit purposes?