Cannot find Unmatched Data via Advanced Filter

Hi, so I thought Advanced Filter will be the way to go for my needs, but I can't seem to get it to list items that are unmatched.

I've attached the example, basically I just used the content of Source as my Criteria Range and just added "<>" as a prefix via a macro (which should lookup those entries that are unmatched). As a list range, I pasted Extract and Source just for the sake of testing, and modified some entries assuming it will find items that are unmatched.

It doesn't appear to be the case however and when I try to filter it out it doesn't display anything aside from the header names on another sheet.

Tried adding "'=" to the prefix but doesn't seem to do the trick either.

Any thoughts?