it's happened before, in '79 and '97. Is Abel running Carb Day tomorrow? He's first alternate, so he should be in case there's a big wreck that they can't bounce back from. Long shot, probably would need to totally write off the tub and no spare available.
in '79 it was a controversy over trying to cheat the popoff valve. After a court hearing USAC allowed 11 cars a 5th day of qualifying, with anyone who could go faster then the 33rd place car an opportunity to tun. Out of the 11, only 2 made it.
In '97 two cars were added as a result of controversy surrounding the IRL's practice of guaranteeing spots for IRL teams. But only 30 took the green as there was a crash on the pace lap eliminating 3 and two wouldn't re-start.
Back in 87 I was assigned to Stan Fox in Foyt's garage. He crashed hard enough to break the tub, but he didn't want to take a backup and go to the rear of the field, so they took it apart, flew it back to England, fixed it, and got it back to indy in time for the car to get assembled. At 0600 on race day they were still putting parts on it.