Unfortunately, this case involved a consequent bank overdraft, this means there really was NO ROOM for "ASAP", as can be clearly seen by the fact the original $50 became $100 due to bank FINES for breach of contract (going overdrawn without permission).
This is made worse by first no reply for a couple of days, then one blaming the customers bank and by implication refusing to do any more about it. If the BANK is really at fault, then the customer MUST approach the bank and ask them to recover the money, thus JF are ASKING this player to initiate a "chargeback" on the grounds of an unauthorised debit. While the bank can be told about the merchant believing the bank to be at fault, all that has happened is that the processors have become the target of an error investigation, something that might reveal what the money was REALLY for, and which could then lead to those processors being identified by the Federal reserve as "criminal (gaming)" - and then they are lost as a deposit & payment method.
The best way to sort this out (it was only $50), is as soon as the player showed the bank statement with the extra $50, get it back to them ASAP as a withdrawal or refunded duplicate charge. Hopefully, the player could convince the bank to forget the extra charges because of the error, and as far as the bank was concerned, this would still be something about VOIP, and not gaming.
While David Brickman seemed to leave something to be desired, it should NEVER have needed to get this far in the first place, CS should have handled this, and whenever promised to reply were given, ensured a reply was forthcoming, even if it was only a progress report.
This is a general problem with JF, when these odd mistakes happen, you really have to FIGHT ALL THE WAY, because no-one at their end seems to oversee the big picture - as soon as promised replies fail to appear, nothing will happen unless you contact them again and press the issue.
I did an experiment once. I was promised a resolution over a stuck withdrawal (normally takes 2 days max). I was promised it would be taken care of "ASAP". Instead of contacting CS again, I just waited to see what happened. Well, after a FORTNIGHT, I decided to end the trial and contact CS - NOTHING had been done

No-one had been tasked with it, my withdrawal was still in limbo. I pressed and bullied away and got a quick reply & my money. It was a "server error" with their processor, which meant they though I had been paid already. There is NO ERROR TRAPPING WHATSOEVER for this eventuality, once it has gone wrong, it stays gone wrong till someone works out where to look for the errors (David in this case, not the CS).
I believe, therefore, the error in the above case really IS at the processor end, and not with the bank - just no-one bothered to look at ALL the traceable evidence from the transaction before deciding to pass the buck to the player's bank.
Particularly for the USA, casinos should NEVER pass the buck and get the player to take it up with the bank, the LAST thing they want is banks looking into these transactions forensically to sort out a reported error.