note that yum goes out to the internet, so you need to allow outbound to RH. Its not a server listening at your end.
There are also 2 official extra RH methods : RH Proxy server, Satellite server. You can check out all the info at the RH website as if you have paid for RH, you have an RHN login avail, even if you normally get support from HP.
Also, if HP can't explain it to you, you can try asking RH, they usually try to help in cases like this. Good PR.