So first, If they did have a "pipe burst" there should be a work order number and a papertrail of the parts that were used. Unless they had valves on their side which they could isolate the break, they would have had to call in their local water department to do a shut off. There would be a record of that as well. Also their connection is metered as well. If there were a pipe burst we should be able to look at their usage and see. Some meters can track the exact time water is used so if they have those types of meters set up we can tell if they are liars