I'm not expert on this but what I'm seeing is that port 443 is serving up a response when jaruzel.com is requested on that port. While you may not be actively advertising that domain with https URLs, it is valid for clients to request one speculatively.
There isn't a valid cert for that domain and for some reason for server is offering a different one. Presumably you need to unbind 443 from that host header name (this is based on memories of configuring IIS a decade ago).
"port 443 is serving up a response when jaruzel.com is requested on that port"
The only response is a 404, which is exactly what should be displayed (to the best of my knowledge) for a domain that isn't configured for that IP/port when there are other sites utilizing that IP/port.
I have an IP... that IP points to a router, that router port-forwards ports 80 and 443 blindly to a web server, on that web server is a bunch of websites. IIS knows which ones to serve to clients based on a) the host-header, and b) the port.
jaruzel.com:443 is not valid, but because I run an older version of IIS[1], that does not support SNI, the cert is bound to the port, not the host-header. As such any domain name that points to the IP will dump you at that cert if you try to connect on port 443.
Complaining about a non-existent SSL cert and then backseat driving the "fix", using words like "you need to", all based on shady memories of configuring IIS a decade ago?
There isn't a valid cert for that domain and for some reason for server is offering a different one. Presumably you need to unbind 443 from that host header name (this is based on memories of configuring IIS a decade ago).