If none of that helps, you might check your picard error log.
Using the exact same settings wouldn't improve things.
Then I looked at the error log, and noticed several entries concerning some failed web access (or matching, sorry, I didn't write it down).
I noticed I had some LastFM plugins present, and I had also experimented a bit with the suggested code from MB Wikia.
Then I decided to uninstall Picard, remove all remaining concerning folders and re-install Picard.
And now it all seems to work.
The only thing that I don't understand yet, is that even though I stripped the Gaucho album from all it's tags, Picard will match it everytime with a certain DTS release, which happens to be about the only one that has no performers mentioned at all.
But at least now I can hand pick another release that has that info, and it's loaded just fine then.
A question about your setting:
You have set encoding to UTF-16
I would be inclined to use UTF-8
Is there a specific reason you have set UTF-16?