So is it working or not? You didn't give an example of something that isn't working. Assuming the folder you mentioned is the same folder where $mircini shows your mirc.ini is located, then the path isn't even needed at all. You can put the filename into %variable3 then confirm whether $isfile(%variable3) is $true or $false. You can also check the value of $readn to see if it's non-zero, because * $+ $null $+ * will match a blank line or even a line containing only spaces, and both will cause echo to fail.
There are another couple cases where the match would fail to return the right thing.
4. when your search string and the file string don't have a substring match due to extra spaces. If the file has 2 spaces between "the" and "house" but your search text only has 1 space, then no match.
5. There is no switch for a case-sensitive match, so if it's matching NICK when you want only a case-sensitive match with Nick, you'd need to use the regex switch r which defaults to case-sensitive, but that uses different syntax than wildcard.