The written Camaro warranty excludes racing and "abuse" and "misuse". Just like all GM vehicles. HPDE may or may not fall under abuse and misuse, depending upon who gets to decide. However, Al Oppenheimer, chief engineer of the Camaro, is on video saying they will cover the Zl1 warranty on the track. This would be just for the Zl1, not the rest of the Camaro line, and is one of the reasons I bought a ZL1.
Will the video hold up in a court or arbitration? Not sure we know that answer. My opinion is GM has every intention of honoring the warranty if the car is not abused, and is driven (stock) at an HPDE event, and we have seen no evidence to the contrary. There are even instructions on track use in the owner's manual, so will be hard to claim that is "misuse" by GM.
EDIT: Here's one of the video's of the statement at the 0:40 mark