What
In Mercury there are no audit logs that show when documents are uploaded or deleted from the Microsoft Dynamics 365 interface. SharePoint audit logs are limited and do not include documents that are deleted directly via Mercury.
NOTE: The instructions in this article can only be carried out with Microsoft Administrator level access.
Where
More comprehensive document auditing information and functionality can be found at https://security.microsoft.com/auditlogsearch, as long as the user has suitable Microsoft Admin rights (NOTE: different from Mercury or Dynamics permissions).
How
This audit search goes beyond the standard Dynamics and SharePoint auditing. Here you can search for a vast range of auditable criteria, including document uploads and deleted documents:
Additional Information > Limitations
Auditable data goes back 90 days only. Microsoft Purview has audit data for up to 10 years, but this is an additional Microsoft product purchase and will not bring up retrospective historical data beyond 90 days prior to the product being purchased and deployed.