How would a sale of Morata even work, considering that Real Madrid has the buyback clause? I am assuming that a percentage of the transfer fee would have to go to RM, and we would need their permission in the first place, I would think.
Strictly speaking, money would only go to Real Madrid if there is a sell-on clause, which would be entirely separate from the buy-back.
Juve could choose to sell Morata at any time and won't need Real's permission. Of course, Real are entitled to activate their buy-back clause, but they've no rights beyond that.
There's only one way I could imagine this really getting complicated:
Say that Liverpool offer was genuine and there was 60m on the table.
Juve may not want to sell or they may choose to take 60m.
Would Real Madrid sit there and let Juve pocket 60m?
In theory they could sign Morata for 35m (or less, possibly) and then immediately transfer him to Liverpool for 60m and pocket a 25m profit (or they could threaten to do that in order to get a chunk of the transfer fee Liverpool were offering Juve).
In theory, all that would prevent that would be Morata refusing the offers and choosing to stay at Juve.
Juve having a good relationship with Real would make such a scenario pretty unlikely, though.