I contacted WYSE about what what ports are required for the management server to function over a firewall, requesting port / protocol / direction. I was told http only.
Well... here's the truth. The client requires BIDIRECTIONAL connectivity on port 50000/tcp to/from the server. From my testing, both the source & destination ports are 50000 regardless of the direction of the connection.
Also, to support firmware updates, the client need to be able to establish a FTP connection (tcp/21) to the management console.
Notice I didn't mention http(s)... Odd . Thanks for the help WYSE!