if there is one definite in this story,,,the boat would leave with a fully charged and load tested battery!,,,the pin,,,if they put it in,,,their error,,,if you put it in,,,your error,,,usually you don’t need a depth finder to know you are in shallow water…in Canada it takes a year to get a ski from a dealer,,,so…not sure in US…maybe therefore keep it,,,and learn from this experience?