To me, i see the Haaland situation as Dortmund refusing to sell up 2 core squad members in the same summer; it is not about the money involved, or the release clause in Haaland contract. It is about keeping the Dortmund squad competitive ahead of a new season.
On the other hand, the Player himself has shown no signs of wanting to leave, and ofcourse not to London. Dortmund would earn huge bucks from Haaland departure; either this summer or next summer
It is true that Haaland doesn't appear on rush to quit Dortmund as Mbappe on PSG but that doesn't mean that he wants to stay there until 2024 imo.
Dortmund is known to farm good players, I mean they pick future top players, make them stars then sell them and so on. They want to compete in European leagues, they want to have the Bundesliga title but they aren't spending a lot to do it.