Originally Posted by
Wx4caster
1. When an operating air carrier reasonably expects to deny boarding on a flight, it shall first call for volunteers to surrender their reservations in exchange for benefits under conditions to be agreed between the passenger concerned and the operating air carrier. Volunteers shall be assisted in accordance with Article 8, such assistance being additional to the benefits mentioned in this paragraph.
$2000 was agreed to and apparently delivered. The fact that your niece and nephew didn’t understand what they were agreeing to is unfortunate but hardly relevant.
ETCs can be used for any traveler, and while it’s against the terms and conditions to exchange them for cash, I assume neither you nor your niece or nephew would go out of your way to mention it.