I remember from your previous posts that you weren't getting any alerts when using Google's DNS servers and the alerts were only there when using your ISP's.
I think it would be prudent to continue using Google's servers.
I don't think your assigned ISP ext. IP address will be infected, but there seems to be something not right when using their DNS servers.
That website is what we use to check if an IP address of someone who has registered on the forum is a known spammer.
You can also enter their email address which may come up with more info.
Try it with your own and then see if anyone has spoofed it - that can happen and then your IP address gets blacklisted, so you would need to change yours which you can do by switching off and unplugging all of the cables from the router for about 30mins, as well as switching off your computer.
Then when you switch the router back on and all of its lights are on, switch the computer back on and
www.speedtest.net will display your new one.
I wouldn't worry too much about your ext. IP address unless you end up blacklisted - that Honeypot website doesn't support what I've found when running those IP addresses with the (S) or the (SD) after them - no suspicious activity.