Team A, has 1st &10 from the B-18 yard line. A24 takes a toss left on a sweep and heads around the left end. As A24 crosses the LOS, A72 is flagged for holding B54 2 yards downfield. A72 continues to hold and “drags” B54 OB at the B-16 yard line. We have an inadvertent whistle before A72 “pancakes” B54 well OB drawing another flag. We have holding on A72, and a DB late hit UNR also on A72. Running back A24 is now in the EZ with a “TD”. What is the correct enforcement here and what rule reference(s) apply?