On the chance that someone does not know from memory, this would be the evening LAX-KOA service.

There is no compensation due, but DL will generally issue a customer service gesture of some SkyMiles.

Check your travel insurance as a 4+ hour delay may result in some standard reimbursement per passenger.

I would only complain about the service if it was abbreviated due to the delay. In other words, if dinner was scheduled and not served, that would likely increase the gesture. The award ticket is irrelevant, your status is not.

This is a bit of a DL fail as F pax should likely have been issued a meal voucher at the Club or gate when the clock kept ticking. On the other hand, this one sounds as though it involved creeping delays and the location of a substitute aircraft, so hard to send people off for a meal.