No matter what Dortmund must be still in a very good position financially. After Bellingham's sale they have made a big amount of money. This is their priority in the end so I don't think they are still thinking about how they can lose their title chance like that. Yeah it was really unbelievable but they are still able to reach their main goals according to their vision.
As long as they make so much money in sales of their players it wouldn't be important for them whether they are champions or not. I assume the fans think the opposite but they must be also aware of Dortmund's policy already. Otherwise Dortmund can easily build a squad that can be much more competitive for the league title to win.
We should not forget that Dortmund was basically bankrupt in the early 2000's because they made so much debts with stupid transfers in the years before that. Then Jürgen Klopp became the coach of Dortmund and then they started to rise again and they won the Bundesliga two times with him and they even made it into the final of the Champions League.
In the last few years it became their business model to buy young talents and then sell them again for high amounts of money.