Haaland is a big part of Dortmund right now. In the absence of him due to an injury, we saw how much Dortmund had a hard time beating their opponents. I mean that they had scoring problems more. Because Haaland has scored most of their goals I guess. Considering this fact, I think that Dortmund would be much weaker than now for sure if they lose Haaland to some other club. I'm pretty sure that Dortmund would do their best to keep him here this summer also but it doesn't seem probable to me.
Of course Dortmund will want to keep Haaland in the team, but will Haaland want that? That's the real question to ask. Haaland's release clause is low. You can find dozens of clubs willing to pay him this money. If Haaland doesn't want to leave then we can talk about different possibilities. However, in my opinion, he must feel closer to Real Madrid in Haaland. For some reason I feel like Real Madrid will sign him.