- I have no problem of crediting an Expedia package to AA and even apply SWUs to the flights but that was a few years ago. You should be able to pull out your itinerary on www.aa.com and chose seats etc. based on your status. The flights may also post as Special Fares (i.e., distance base). You can search for American Airlines Special Fares and read the description. In my past experience it was hard to determine how miles will be posting before taking the flights.
However, I will advise against booking through AA Vacation. Starting March 1, 2023 if you Gold and above, you will be earning 5 miles/loyalty points per dollar of the total vacation package cost minus taxes and (it looks like) some hotel fees divided equally between you and other individuals in the booking. I still have to see an example of earning more miles and LPs with AAVacations vs. a separate booking. Of course, YMMV especially if you are saving $500. With AA vacations you will be getting all the benefits as booking with AA directly except screwed miles and LP credits. Personally, i would go with Orbitz especially if there is a chance to get distance based credit for the flights to earn more vs. fare-based credits. Do not forget to book the Orbitz package through one of the shopping portals (like Top Cashback) to get additional up to 4% cash back for the booking.
One possible problem is that in case of schedule change etc. AA may ask you to deal with Orbitz but I never had such a problem in the past when going through EXP desk. Of course, this could change any time.