Chris's hair color changes between yellow and semi-green multiple times.
Whilst on the bus after running from the synagogue Peter takes off his kippah and it's in his hand. In the next clip it is back on his head.
Upon the arrival in Las Vegas, the MGM Grand and Luxor (pyramid) hotel/casino are shown to be on the same side of the road and relatively close to one another. In actuality these hotel/casinos are on opposite sides of the street from one another, and even then there is a major intersection between them.
Peter and Chris are already in Las Vegas, waiting in line at the Bar Mitzvah Chapel when Lois learns where they've gone. She makes the two-day drive to Nevada and runs three miles to Las Vegas while they're still waiting.