The tanker is meant to be carrying 20 000 000 gallons of LNG. The 'tanker' they use is a tug boat fitted with fake tanks. If full, they would have a capacity of roughly 100 000 gallons. A real LNG tanker is about 20 times the size.
Just past the half way point, Cabe is asked about a military ship to help with their situation, and he states that the nearest ship is in the Gulf of Mexico. Which has the lower isthmus of the continent of North America between it and the west coast in California where the incident the team is dealing with is supposedly taking place. The ship would have to sail down to Panama & then cross the canal and steam up to the US west coast if that was the "nearest" ship, meaning that a ship in Hawaii would literally be closer. Contrary to the Cabe's assertion, no ship in the Gulf of Mexico would be able to help even if they had 3 days to work with, let alone an hour or so. It would make more sense to ask Canada to send a ship from Vancouver BC at that point.