@awsick
That is indeed weird.
I've had three different Archer routers with OpenVPN server and it always worked fine with the default settings.
I also cannot find any other posts of users mentioning problems with the OpenVPN server of the Archer GX90. (that's the model name of your AX6600 router, isn't it?)
As a last resort you could test if things improve after performing a full "Factory Restore" on the router. Best would be to configure only the Internet connection settings of the router and then continue straight with the OpenVPN server's setup and testing.
To reduce the effort of bringing the router back to it's previous state in case the factory restore doesn't improve anything with regards to the OpenVPN server, you should first do a "Backup" of the router's present settings and later you can then "Restore" the old settings using the backup file.