I really think people are over-complicating the matter tbh.
If a player has a release clause of x, you pay x, and the player signs, selling club has no say in it.
If a player has a clause of x, but you don't really want to pay x all in one go, so you negotiate a payment plan with the selling club over a number of years, maybe even paying more in total than the clause figure, which the selling club has to agree to, then you haven't activated the release clause at all, you've just negotiated a transfer like normal, using the release clause figure as a loose guide for negotiations.
That is exactly what we did with Porro. If it's what we were hoping to do with MGW, then we had absolutely no business getting him down for a medical and fully agreeing terms with him.
To me, the way in which things unfolded from Thursday evening to now, the only way it makes sense is if we were just activating the clause and lumping £60m to Forest, which admittedly does seem out of character for Levy/us.