The uncertain is a catch all for anything they can't quite figure out. I have 9%.
AS far a s matches the other company you mention because they have a medical component at tracks lots of endogamous populations because they have more inherited medical issues.
That being said because they phase results here you are not as likely to get false matches as elsewhere. You also need to go further down your match list. I have found 44 confirmed matches and some of them are at the lowest confidence level. So keep looking. Do not depend on the list of matching names. glance through each list as a simple spelling change will not find the match.