Since this actually seems to be a server related issue, it would be better suited for stackoverflow.com, or a stack exchange that is dedicated to networking.
But, I’ll do my best to help here.
If the CURL is showing connection refused, the connection is getting blocked before it can even load WP. You could prove this by making a file in the root that just has phpinfo() and attempting to access it directly.
My guess is that the server is not configured to listen to the web ports. This would explain why you can access the server over your SSH port but not over the web.