I think this will play out in a similar way to the Grealish transfer.
Spurs will go to Kane with a new contract and have meetings to try and get him to stay. Kane will reiterate that he would rather pull out rusty nails with his teeth than be top scorer in the Europa Conference League. Tottenham will realise that the money is worth more than one more year with an unhappy player and half the money next summer. They'll come to the table, do some hard bargaining, and get the top dollar that they want because we're kind of over a barrel here. It'll end with Nuno spending £100m to build a mediocre team, Levy spending the next year masturbating over the fact that he made City meet his tough valuation, and City winning the league with Kane having no idea what to do at the trophy presentation.