Well, the nginx http proxy was just that easy. I can point my browser at it and the witness responds: 
11 eof_exception: End Of File
stringstream
    {}
    th_a  sstream.cpp:109 peek
    {"str":""}
    th_a  json.cpp:478 from_string
That's using an https:// prefix. If I use wss:// that's a different story. 
How are you doing the proxy for 
https://bitshares.openledger.info/ ?
What web server are you using?
Will another protocol definition be required?
Here's the nginx config that proxied the https --> rpc:8090
server {
        listen 443 ssl;
        server_name thom.domain.mine;
        ssl on;
        ssl_certificate /etc/nginx/ssl/certs/server.crt;
        ssl_certificate_key /etc/nginx/ssl/private/server.key;
        ssl_session_cache shared:SSL:1m;
        ssl_session_timeout 5m;
#       ssl_protocols SSLv3 TLSv1 TLSv1.1 TLSv1.2;
#       ssl_ciphers "HIGH:!aNULL:!MD5 or HIGH:!aNULL:!MD5:!3DES";
#       ssl_prefer_server_ciphers on;
       location /wallet {
                proxy_pass http://localhost:8090;
       }
}