I personally believe that Haaland is an opportunistic player, and hell be switching clubs constantly and that was a key reason why Real Madrid didnt target him but now they have an excellent chance to sweep in and take him to La Liga. Furthermore I feel that even Kane isnt a bad signing provided they can strike a deal with Tottenham, because he can guarantee them goals and he has lots of experience too which will further improve the team.
I think he may stay for another season, that way he would not be the type of player who left after just one season and a bad news, but he would be there "if" something happens, there is a likely chance something could happen, but he would be basically saying he stayed around.
This of course depends on what the punishment is, if they are sent below to championship, he won't stay but neither majority of the players, many will leave so it will be fine. In that situation Real could scoop in and buy him, whatever his price is, if he is 200 million then they will pay that, it really doesn't matter how much he is because he is a one of a kind player you can't find anywhere else.