I set up 3 different emails for forwarding from my custom domain to the same gmail account, but even though the logs say emails are being forwarded, I am only receiving email for one of the accounts.
Made sure mx records do not contain foreign entries and checked the logs that there were no errors forwarding the email accounts in question.
When the status stays “Forwarded”, it means that the final destination, e.g. in your case, Google (Gmail), has accepted the message on their end, with a status code for successful delivery.
Any further troubleshooting after that, such as e.g. if you’re missing emails as it sounds, would then be something you need to do together with Google, and from their end, as they took a message in, which vanished afterwards.
That said, -
Are you sending emails from “[email protected]” to an Email Routing address, which is forwarding to “[email protected]”, when you’re testing this?
Gmail have previously been known for de-duplicating messages, which means if the same message already exist (e.g. in your Sent folder), then it won’t turn up in your Inbox, as you already have that exact message elsewhere.
If you wish to test the email routing, the only recommended way would be to be sending from a completely different email address, that has absolutely nothing to do with your Email Routing set up.
Oh man that seems to be it. Thank you so much for your help! Google ftl sometimes 
. Awesome advice!