I'm sorry to hear about your experience.

Ticketing on AA normally can take up to two days, but you can ask for immediate ticketing and wait on hold. Be insistent, maybe tell them that you're concerned about possible price increases. After two days when I still didn't have a ticket number on my DONE3 last week, I called the RTW desk and asked for immediate ticketing. It was ticketed (with a ticket number) while I waited on hold. Remember, it's not ticketed until there's a ticket number.

I've done more than a dozen xONEx tickets over the years, both AONEs and DONEs and never had a hold placed on my credit card. No idea what that's about.

Finally, read carefully the rules and warnings that you'll get by email both when you first book and receive the itinerary by email, and with your ticket. That's what they're there for. From a legal perspective (yes, IAAL) no telephone agent has the authority to alter the published/printed terms and conditions. So if you're told that your fare is locked in, you now know to rely on the printed Ts & Cs, not what you're told on the phone.