Alright. Time for the important stuff.
4:26 - Z Coordinate starts at 124 and decreases below 122
4:29 - Z Coordinate is at 124 again and decreases below 122 a second time
4:32 - Z Coordinate is at 124 for the THIRD TIME and immediately starts decreasing again
4:38 - The thing has moved for another 6 seconds now and the Z Coordinate once again begins at 124 before it slowly decreases.
They thought we wouldn't notice. But they underestimated us - we DID notice! Sloppy editing - EXPOSED!
/edit: Also @5:13 the guys in the background don't cast shadows. Tzezezeze.