Parental controls are disabled. I spent a long time on an online chat with TP-Link support and reset the router to factory default settings among other things they had me check/try and still can't access that web site. In the end they asked me to check and turn off any potential firewalls on my modem. So another chat with my cable tech support verified that there is no firewall built into my modem.
Next will be another session with TP-Link support. I got the feeling that they have no clue what is blocking it and I've got no clue either. All I know is that anything I connect up to the router can't access and anything I use to bypass the router can access it?!?!?!?!?!?