I found 3 nicks using ipv6 addresses, and I was able to suppress their VERSION reply using "/ignore Nickname 2" which generates the last line of your ignore list. It didn't matter that 2 of the 3 had consecutive :: in their address. Their /away message still leaked through, but that is to be expected because this comes from raw 301, where $nick is $server.
I tested on the 7.51 beta, but I get the same results in 6.35.
Also, make sure this answers that it's a match:
//if (*!*@2a02:a03f:1a18:4600:176:52b0:baaa:71b9 iswm $address(NickGoesHere,5)) echo -a match | else echo -a no match
Another possibility is the accented vowel in the $network value. Try editing the entry to remove the name of the network, to see if that fixes it. Though that shouldn't cause a problem for this nick without affecting the others.