Could they not just hire trainees as all new hires and bond them for some token level of training outside of the EBA?
They don't even need to do that. Apart from maybe Cathay, new hire trainees generally can't go anywhere anyway. Look at Virgin just recently. Requirements for an SO were put up to 500 multi command. Half the current FO's can't even apply. That's why the company wouldn't need to worry about a financial bond for new hires. If they get trainees they'll be stuck there anyway.