This is an old problem with EI. When I was EXP my EI boarding cards still showed "Ruby" even though I hadn't been Gold for many years. As you noted, EI agents usually rely on your card rather than the status on the boarding card for lounge access etc so the only impact is on one's vanity.
In your case the glitch worked in your favour.
Eligible EI flights have always posted fairly promptly to my accounts, IIRC within 3-4 days or so. The earning classes on EI are relatively restricted so check it's an eligible fare and also make sure that your AA no. appeared on the boarding card as EI check-in agents can be lax at entering it on the system. In any case give it another few days before contacting AA.