Character mistake: McGarrett's team is in place for an assault. One of the members spots the "Rosita", a ship, not a person as they expected. But he calls it a Panamax ship, which it definitely is not. It is a smallish container ship, incapable of hauling 4,500 containers as a Panamax ship could. (00:23:57)
Factual error: McGarrett is reviewing a brief on a suspected cartel operative. He shows a picture and says it is called a "tela de araña" saying it is a spider web. Wrong. A spider web in Spanish is a "telaraña", all one word. (00:05:13)
Factual error: A man gets out of his car and identifies himself as a Special Agent. He shows McGarrett a badge and an ID card identifying him as a Special Agent of the CIA. There is no such thing. The CIA does not have Special Agents. They have Operations Officers. And it would be extremely unlikely they would have a badge, as they are not law enforcement officers. (00:01:45)
Factual error: The plane taking McGarrett from Panama to Mexico purports to be owned by a Mexican fishing company. But the registration number on the plane starts with an N and has 5 numbers and a letter. First of all, a Mexican aircraft would not have a registration number starting with an N. That is reserved for aircraft of US registry. All that aside, the registration number is invalid. US aircraft have at most five characters after the N. The registration - as I suspected - was shown to be in an invalid format when queried in the Federal Aviation Administration database. (00:11:18)
Chosen answer: They are Junior's SEAL buddies.