The rumour at the time was that Bally had big gambling debts that were about to become public, the club, supposedly paid them off and sold Bally and took their money back from his percentage of the transfer fee, in those days a player was entitled to a share of the fee provided he had not asked for a transfer.
In my opinion that is all it was, a rumour, the real reason for his move was 'the cat'. Catterick liked to shake things up a bit and keep the players on the back foot. He thought that selling Bally for over £200,000 was good business and sent out a message to the dressing room that he was still the man even after his recent health problems. Again, in my opinion, he made the biggest mistake of his Everton career.