I don't how to explain that. But here's another example. When I got my Last SRT-4 it came off the truck with 0 miles. The odometer said 0000000, but the trip odometer said .8 miles. So the trip was higher than the odometer until it rolled over to one mile. That's probably what happen here. True story. I think the car is ok.

The other thing is modern cars with digital odometers cannot be reset or rolled back. The mileage is stored in a minimum of 4 places in the electrical system. The ECU, ABS, BCM, and gauge cluster all store it. There is also supposed to be another unknown place that it is stored that only the car itself knows. You would have to replace all four of these components and find the secret hiding place in the electrical system in order to roll back the mileage. So, basically it's impossible unless the car was in a flood and had all that redone...