this is a good move because if you look at it now there really is no reason for haaland to stay at dortmund and most likely he will leave and switch to another club that does have a high enough chance of winning the league.
dortmund's move to increase his salary is quite good because this could be one of the reasons for him to stay even if it seems difficult because he could be at a new club getting something interesting.
but on the other hand this is a pretty difficult one because even though Haaland is one of the great young players at the moment, but for performance at a new club (if he moves) it is something that is quite risky because of course there will be adjustments again with the team and colleagues in new team.