Well I sure haven't seem the vast majority of routers out there, "but" since the WCCK was intended to be setup from a DirecTV receiver, I don't get/see how if all the entries are correct and it links, why the router would not give internet access, "unless" as this comcrap has, a level of parental controls that need attention.
It has a WPS button on it for that reason actually. The easiest, and preferred, method from a DIRECTV standpoint is to use that button. Then nothing has to be done from a settings standpoing 99.9% of the time.
The software in the receiver was designed for use with the wireless adapters that were built prior to the WPS. Either way can and should work.
Who knows what is going on inside that router which is stopping it. Unfortunately there are many scenarios and doing it over a forum is not very easy unless it's real time and then it's still not the best medium.