Have you included ARC support for forwarded email? This is pretty important for not getting blocked as spam when there's strict DMARC enforcement while also not getting your "friendly-from" blacklisted as a spammer.
At the moment received emails are piped to the application where they are then forwarded on as a new email from an AnonAddy domain. So they currently pass SPF and DKIM checks as my DMARC reports show.