It's what happens when you leave things to the last few hours before the transfer window closes. Palace pulled the plug because the signing they were making as Guehi's replacement joined West Ham instead so left no time to sign another replacement.
I don’t get this argument that it justifies players behaving terribly. Guehi didn’t go because Palace didn’t get the replacement they wanted. If for example Wissa failed his medical or another club would have offered more money to Brentford then Isak wouldn’t have been sold to Liverpool.