My father is on flight 53 LAX-HOU-EZE

It was supposed to leave at 2:30 pm and connect to EZE, but, they were informed that due to mechanical problems, the flight was delayed 2 hours.

This means that his connection to EZE is gone. The next available is on the 23rd at 9 pm, arriving on the 24th.

I called CO Plat to better inform myself on the situation and see what he can expect since I don't know the IDB rules on CO... and the rep claims that the flight was delayed due to weather, thunderstorms in Houston...

I know that airlines use this wild card to get out of everything.. frustrating.

He lands in Houston in a couple of hours .. I told him not to leave the airport without some form of compensation. Aside from asking to get booked on an earlier flight on another carrier, what else can he get? I was aiming for a voucher for credit, but that may be a long shot at this point

ideas?