From who did the offers come?
I don't know when and if another offer will come in but there is still a lot of time the transfer window just opened. Regardless, I think that we should sell at the price that we are happy to accept. 15m seems too low for a player of Maignan's calibre. 25m would be OK, but that's just me.
There were two different EPL offers for Kessie in preceding years, think both were midtable clubs. I want to say Wolves, can't remember the other.
If we wait then that means we probably may have to carry him for next season. For fans that hope that may seem ok but obviously for management that is loss of sale and incurring more wages. For a coach that can mean dealing with an unhappy player that was part of the old culture while you are trying to change things.
What also if you have to play him and things aren't improving for him personally, just makes the situation more tricky.
I think a clean break is best. If Rafa stays it is fine as you can live with his flaws easier than the others.
He is also the furthest away from termination and the youngest so plausibly another good offer can materialise for him.