Port 80 is the standard browser port. the cam must be on a higher number. even the documentation for the cam suggests over 6000 or 8000 .
when you run the whatsmyip and it gives you a number that's just the internet side of the router. You now need the port assigned to the cam. If its not shown on the cam app then you need to look in the router for the assigned port. it is possible the router does not have the port and it is only shown on the cam app.