In order to debug, you should first check the Ingress-Nginx logs and see what exactly the error is:
$ kubectl logs -n nginx-ingress-ns nginx-ingress-controller-blahblahpod
It will allow you to pinpoint the error, and you can see if a new nginx.conf was even generated. Since you are grepping ssl_client and nothing is found, means there is an error somewhere that prevented nginx.conf from loading your ingress resource.
PS: I also updated the guide and changed how the certificates are generated.