Because you're serving the website on a non-standard port, you will always need to provide the port in the web browser.
That said, I don't see anything wrong here. It looks like you've got the right ports set, TCP should be correct. You may not get a ping, because ICMP is likely not enabled at the modem. When you ping, you ping the first device that's exposed to the internet, not an open server.
Just to be sure, when you're on your phone, you're using data? If you're on wi-fi, the modem/router may not be configured to perform NAT reflection, so you won't be able to access anything via your WAN IP.
The problem is they didn't initiate the DMCA process at all, nor did the report submitted have anything to do with Copyright Infringement. They submitted a fraud/phishing report, as if the domain itself was serving or facilitating malicious content harmful to someone who visits it.. So forget the DMCA process, this was straight up just corner cutting on the part of the firm representing Funko that misrepresented the nature of the situation as a whole.