Stupidity: As the position of the Tiger was perpendicular to the Sherman platoon's line of march, and they were advancing across totally open country with firm ground all around, it didn't matter a hill of beans whether they shot the first or the last tank in the column.
Suggested correction: You really didn't explain the context here. Was there a big discussion of which tank to shoot first?
The mistake is saying that the tank column was travelling through an open field. It wouldn't matter if Tiger 131 hit the lead or rear tank in the column as they could manoeuvre around the disabled tank. A somewhat valid point.
You missed the point of the correction. Is it shown in the movie that they specifically targeted the first tank?
Stupidity: In the exciting denouement when the SS company approach the ostensibly disabled Sherman, the SS would have just walked around it. A burning tank was a common occurrence. I doubt they would start climbing on it and they certainly wouldn't start charging at it individually as to get mowed down. The SS were well trained units. Such stupidity is unlikely.