Yeah, I gave up because it wasn’t really necessary for me. I have a /29 plus I can open ports so I just decided to set up an SMTP relay on my VPS because my ISP blocks outbound on port 25. I can still do inbound on port 25 so no issues receiving emails. It actually might benefit you to have an SMTP relay on the VPS to properly route the outbound email if you don’t want to have two Wireguard tunnels running.