Ok, so connection isn't the issue. Next step is to check if it's related with the DNS (resolv the pool domain) or some port blocking in the router.

With a computer behind the route (use the same that bitaxe), could you try to resolv the pool domain? search for curl in case you want to test.

I am not focusing in bitaxe configuration because you said that using another network, without any change, the bitaxe works.