Scaredy-Cats? Or Some Deeper Explanation?

This Texas "Lake Pirates" story gets stranger every day. Something's not right about it: it smells like a "Lake Pirate":

The family of the man reportedly killed on the Mexican side of Falcon Lake on the Texas border has been publicly pleading that American officials be allowed to cross over the border to search for his body. But the Sheriff leading the investigation on the U.S. side told Today this morning that Mexican officials invited his office to participate in the search last night, but that he declined the offer "because it's dangerous."

...When host Meredith Vieira asked if he thought Mexican authorities were hindering the investigation, the border hawkish Zapata County Sheriff Sigifredo Gonzalez said, "Well, it's a custom, I guess you could say, to some extent, to hinder the investigation." But he said he had spoken to a Mexican state police official last night, who told him that Mexican authorities had been out on Friday and Saturday searching for David Hartley's body. Gonzalez said the same official told him that "today, starting around 10 o'clock this morning they're going to have several boats, helicopters, ski jets, looking in that area all over again. And they're not going to stop until they find something, or until all efforts have been exhausted." Gonzalez also said a "very high ranking" official from the attorney general's office in Mexico would be flying to area today by noon today.

Then Vieira asked the sheriff if he'd prefer for his staff to be included in the search. Gonzalez said that, actually, he'd turned down an offer to cross the border to assist.

"Well, it's not necessarily that we're being left out," Gonzalez said. "We have been invited to participate, just last night, to actually go to Mexico and participate. We have chosen, however, to remain here, simply because it's dangerous. It's not that we don't want to go, or we cannot protect ourselves, I'm sure that we can get the assets to go to Mexico. But, I think if we go out there and we end up getting into a gun battle, it's definitely an international incident that would have some repercussions."