Revealing mistake: Just before the truck slides off the cliff edge, you can see that the truck's cab door is open where the driver jumped out.
Revealing mistake: At the reptile farm, the phone booth Mann uses to try and call for help has no phone lines attached to it, above or below ground (you can see that there are no underground wires when the truck mows the booth down). It's definitely not a wireless/radio telephone, either. There should be lines running to it, but there are none. (00:57:00)