You wouldn't have paid anything like $68k. As mentioned in the article, those prices are inflated for charging the insurance company, who in turn negotiates a much better actual price. Similarly, the hospital would have likely worked out a better deal with you. Or, if you qualified (and it sounds like you would have), then Medicaid would have initially picked up the tab and they would have negotiated a better deal for themselves.
In none of these scenarios does anybody actually pay the made-up $68k number.
The hospital would have worked out a better deal with you if you asked. However, if you don't ask, and just put yourself horribly into hock to pay them, they'll take the money. Likewise, if you refuse to pay, and they have to go to collections or the like, they'll apply the full, inflated amount.
Possibly, but look at the picture of the sliced out tendon. ACL replacement is an inherently complicated operation, from a highly skilled practitioner. The take-away from that is: you can't afford to play a dangerous sport like rugby if $5-7k is financially crippling.
In none of these scenarios does anybody actually pay the made-up $68k number.