On jet skis? What not a boat? The couple was stopped by a cop on their way to the lake - something about a tail light on the trailer or something, and they told the cop they were headed to Falcon Lake to go jet skiing. Would it be practical for her to bring a gun out on a jet ski? If she killed her husband, what happened to his body and the jet ski? Why would the witness lie. Could she be telling the truth?
Could be they were just too ignorant to know the danger they put themselves in venturing into the Mexican side of the lake.
Why didn't HE try to stop them ??