The club were completely aware that they had a fight on their hands to keep him but I'm certain that they didn't expect to lose him this window.
Had they known about it they'd have been much better prepared to sign a replacement.
Sticking a caretaker in place was never going to convince him to stay. Giving a caretaker 30 million to spend when the players and system might not be wanted by the new boss still left to much uncertainty in my opinion for a player already seeking assurances and having them fail/lied to.