Higuain needs to agree to go to Spurs, Asa. If we or Juventus are seriously in for him, he might refuse to go there and opt for one of the two other teams and Madrid may just replace him with money they'll get from us/Juve in the deal.
If 40 mill + Higuain is tough to turn down for Spurs, so is 60-63 million. And they can, finaly, buy the Brazilian striker they get linked to, every year.