Originally Posted by
Often1
Without the exact details of what happened at ATL, it is impossible to say anything with certainty. Nut, if the GA had your friend's origin somehow cancelled the second segment, IDB is off the table.
There is no entitlement to anything else. The rest is all a customer service gesture and not compensation. So, the question becomes how much of an inconvenience was all of this.
The problem with this reasoning is that an airline could just cancel segments whenever a flight is oversold and thus avoid being responsible for either IDB or VDB payments. Earlier in the day the OP had a ticket and reservation; the OP apparently checked in for both segments without any problems and at that time had both boarding passes. It certainly should not be the OP's problem or responsibility that the GA canceled the segment when this shouldn't have happened and moreover the GA failed to notify the OP that something bad had been done to the OP's PNR/ticket, so that the error wasn't discovered until the OP tried to board the second segment.