Complex sentence: The DEA and Customs pointed out inaccuracies in the script and gave them access the border checkpoint to Mexico as shown in the film when Wakefield and his people talk with border officials, but did not try to influence the content of the script.
Split into simpler sentences: The DEA and Customs pointed out inaccuracies in the script and gave them access the border checkpoint to Mexico, as shown in the film during the scene in which Wakefield and his people talk with border officials. Despite the assistance, the DEA did not try to influence the content of the script.