As per my support team ticket #686065
Notifications emails that are sent to guest reviewers for updated files/proofs do not have a customized logo, as per the Account Settings.
ie. The invitation email is branded using the uploaded company logo. Follow up notifications when a file/proof is updated show Wrike branding .
This can be very confusing for approvers external to the Wrike user base, as branding changes for the same review request between notifications.