The scenario for determining to qualify for the Champions League in this way will not benefit Dortmund even though they still have a chance. Frankfurt, Freiburg and Dortmund will fight to get a ticket to the Champions League which is determined in the last match. Dortmund will not be too difficult in this match because they will face Kiel as the bottom of the relegation zone. A big win needs to be achieved by Dortmund because if Frankfurt's match against Freiburg ends in a draw it will benefit them.
Yup Dortmund have no other choice they have to win today and another fact even if they win it's not safe enough they have to wait for Freiburg to lose or draw, if Freiburg win then Dortmund hopes for the Champions League next season will be in vain. In this situation I agree with you that Dortmund are likely to score a lot of goals meanwhile for Holstein Kiel this match means nothing there is no way out of degradation.
Anyway, because this is the last match, we have to pay attention to the teams that are still chasing points for a place and I can see almost all home teams have a chance to win. Dortmund and Freiburg aiming for UCL tickets, Mainz and Leipzig eye Europa League tickets well these 4 teams deserve to win and are suitable for parlay bets. Regarding Bayern Munich, not sure if they need the win since confirmed win the title.