Probably a mediawiki-title bug?
$ echo '[[MeatBall:Soft<>"Security]]' | php maintenance/parse.php <div class="mw-parser-output"><p>[[MeatBall:Soft<>"Security]] </p></div>
but
$ echo '[[MeatBall:Soft<>"Security]]' | bin/parse.js --normalize <p><a href='http://meatballwiki.org/wiki/Soft<>"Security' title='meatball:Soft<>"Security'>MeatBall:Soft<>"Security</a></p>