The result does not entirely depend on Freiburg, I mean Dortmund can qualify for the UCL on their own accord even though Freiburg beats Frankfurt. Dortmund must try to win big from Kiel at least 4-0 so even if Freiburg wins Dortmund can still get the top 4 because they win the goal difference over Frankfurt if the result is the opposite or Freiburg loses, they only need to win by a few goals over Kiel. So at this moment it depends on how they live it whether they will depend on Freiburg vs Frankfurt results or want to try with their own strength.
You're very right but sometimes I do see this Dortmund of team as jokers, they like messing up for no just reason, they are good at winning when you don't expect it and lose to teams that we don't expect to win them, this is a team that is not supposed to be struggling to be in the 4th position, Dortmund is among the top four in the German bundles Liga which means they are not supposed to be in this kind of messy situation, they didn't impress me this season, how would they allow themselves to be in the situation of probably having to qualify based on either goal differences.
With the situation on ground, how sure are we sure that Dortmund will win kiel, personally I don't trust Dortmund for some reasons best known to me although let's see what they got, it is now obvious that their destiny is in their hands now but how will the be able to scale through becomes the question.