My advice, based on, well, my experience:
1) No need to treat the fish for the first week unless it is visibly ill - give it a week to settle into QT. A nice quiet tank and turning of all flow during feeding time will allow the fish to to find, sniff, and then eat food. I've had great luck with NLS as a first food.
2) I greatly prefer hypo to copper; as you have found copper can cause lock jaw
3) All fish must be treated for flukes/internal parasites nowadays. This was not needed 5-10 years ago, but it is now. Not sure why. I use Prazi and then Metronidazole, and feed with Metronidazole food.
4) With the hypo, Prazi, Metro, etc...the fish will need to be in QT for 8 weeks.
5) Depending on the size of your QT, do 25% water changes daily and re-dose meds in the proper amount. I usually QT in a 20 gallons and do 50% water changes daily.
Try and get the first eating before you bombard it with meds. Even the most mild of meds (Prazi) can cause lock jaw so better to put a little wait on the fish before he undergoes the process. If you must treat with something to fight ich, etc, I've found Quinine Sulfate to work better and cause less issues than Copper.
Good luck!