Is there a way to audit by whom/when access was granted to Delegated Reviewers in Talent Review

For Talent Review we have it set up so reviewers can Grant Access to subordinate managers to carry out the review as a Delegated Reviewer.

When access has been granted like this, is there anywhere that shows who granted the access/when?

We have employees saying people who have the access when it hasn't been granted, so I'm trying to establish if there is actually a system issue or it's user error.

thank you

(Currently 25b, 25c as of next week)