“At the initial point of the investigation, Vasquez had no reason to fear anything and had no reason to withhold anything.”
Huh? He engaged in the cover up and tampered with evidence by retrieving the spent shell casings. He had plenty to keep quiet about.
You can’t be this dense.
Talking about dense, don't you read? Vasquez appeared of his own volition the day after the investigators appeared in March. He came with a lawyer, obtained a Proffer letter, and told of his retrieval and disposal of the casings. So what was he quiet about concerning his involvement?