The 406 mHz EPIRBs are completely satellite-based and NOAA, upon receiving a position, notify the nearest Coast Guard Sector (or other nation's rescue service).  The old 121.5 mHz EPIRBs were essentially radios that broadcast a distress signal.  If they had an old-style EPIRB, they're correct - only a nearby vessel would pick up the signal.  Satellites pick up the signals on the new-style units and while it takes some time to determine the specific position of the EPIRB, the info is accurate to within 2-5 NM.  I think these two had little or no idea what they were getting into and perhaps planned from the beginning to weave a real sea yarn.