We have a case where a student is adamant that he completed a peer-assessment of a Workshop activity, though no review is shown on his name and the report logs for the course and activity indicated that he did not complete the peer-assessment or even viewed all the submissions made by his peers.
However, he has now send us a screenshot of the submission documents of his peers on his computer, with the time and date stamp of when he downloaded the documents to his computer. On Moodle we can see that he accessed the course and the Workshop activity a minute before the first file was saved on this computer, but the report does not contain any logs indicating that he opened the submissions of his peers.
(The report below is for the course, for the specific student and for the whole of the day in question and all activities and actions; these two entries below are the only actions/activities done (and logged) by the student on the specific day).
This now opens a whole can of worms, because if he was able to download the documents without Moodle having a log for it, then he can argue that he did in fact do the peer-assessments for each student, even though Moodle has no log or activity history/grade of this.
Can the report logs be wrong? It is possible that the student did in fact perform an action that is not in Moodle's logs?