Essentially, AA may be treating the flight like a hidden city issue, and would only allow an
active AA account to claim the miles retroactively upon completion of the itinerary. Your friend is asking AAdvantage reps to turn a blind eye to two significant rules.
You may accrue mileage only for purchased, eligible, published-fare tickets on qualifying routes used in accordance with all applicable conditions of carriage, tariffs, rules and terms of ticketing and travel. AAdvantage mileage accrual eligibility on airline participant routes is subject to change without notice.
Hidden city violates this rule.
and
You may request mileage credit for past, eligible transactions up to 12 months from the transaction date. Transactions prior to your enrollment date are not eligible for mileage credit.