I can understand not wanting to lump all or any of the blame on him, because Koeman was very heavy-handed with this.
But feeling sorry for Barkley?
Come on, now, it's all getting a bit creepy.
He's run his contract down and refused a pay rise.
At his lifelong, boyhood club.
Said boyhood club then agreed a decent fee for him with the English Champions.
He then changed his mind at the last minute (pretty much)
He will now get rehabbed and handsomely paid by said boyhood club, until his injury is healed.
He will then sign for another club in January for a far reduced fee than the one that was agreed before he snubbed the transfer.
Or he will stay at said boyhood club for a further six months, still pulling a handsome wage, and then leave for absolutely free, and get an enormous signing on fee for him and his agent, and his boyhood club, who coached, nurtured, and looked after him, will get no recompense whatsover.
So yeah, by all means, you don't have to blame him.
But don't feel sorry for him.
He's doing fine out of this.