I wanted to test the OpenVPN server on this same device, so I initialized that, and forwarded appropriate ports. Which worked fine. Stopped ovpn and updated wg to run on 1194 and voila it worked. Stopped Wg and updated to original port, and again, it worked.

So, my guess here is that initializing the OpenVPN server on the device triggered something to make wg work.

In case you need info to see if there’s anything, Version
3.027 on the MT300A.

Thanks again Alfie for jumping in here.