I listened to Steve O'Donnell on NASCAR radio. He stated that "the call could have gone both ways" and that either would have been correct. Nice to have "rules" you can bend to give an excuse for anyway NASCAR wants it to go. Example, the 9 car is in the lead. We throw the caution. The 18 or the 41 is in the lead. We monitored the situation and decided to race back to the checkered flag.
The call might have had something to do with how boring that race was too. Nothing like watching single file racing lap, after lap, after lap, after lap, after lap, after lap, after lap, after after lap, after lap, after lap.
Choo Choo