Blind Rage - S3-E2
Revealing mistake: During his first transformation, the Hulk gets behind two soldiers and smiles twice. His second smile is too broad and reveals a very shiny silver tooth filling on his right lower jaw. David does have fillings but they do not cover the external area of the teeth (Ref: when he hugs Katie at the end of the 2nd part of Prometheus, right after his last transformation).
Blind Rage - S3-E2
Revealing mistake: While pushing back the tank, the Hulk seems to be wearing light green loafers.
Brain Child - S3-E3
Continuity mistake: When David leaves at the end he's wearing beige pants, but in the next shot he's wearing dark pants.
Visible crew/equipment: When Colleen is driving cab you can see somebody's fingers on the seat behind her.
Answer: The Hulk is accused of killing Dr. David Banner and Dr. Elenia Marks. After the lab explodes, McGee sees the Hulk emerge carrying the body of Dr. Marks, so he assumed the creature is guilty. It was McGee who caused the explosion. After following the trail of evidence of the Hulk to the lab, he hides when David and Elania arrive. In a darkened storage closet, he knocks over a bottle of flammable liquid. He confronts them, then is forced to leave by Banner, who says, "Don't make me angry, you wouldn't like me when I'm angry." When Banner reenters the lab, it explodes, caused by the Hulk when it went on a rampage trashing the lab, causing many electrical systems to catch fire, thus igniting the flammable liquid.