Believe both the EPIRB and liferaft would be on hydro releases....but sometimes foul due to poor locations and don't float free.
The EPIRB went off...and unless tethered to the boat (bad idea) ...just because it wasn't found..well having looked for them in the open sea, rough weather...not surprising. Plus news reporting on technical issues are often less than desired.
From CFRs....
§ 28.125 Stowage of survival craft. (a) Each inflatable liferaft required to be equipped with a SOLAS A or a SOLAS B equipment pack must be stowed so as to float free and automatically inflate in the event the vessel sinks.
§ 25.26-5 Commercial fishing industry vessels.
(a) The owner of a fishing vessel, a fish processing vessel, or a fish tender vessel, 11 meters (36 feet) or more in
length, except for vessels described in paragraph (b) or (c) of this section, shall ensure that the vessel does not operate on the
high seas or beyond three miles from the coastline of the Great Lakes unless it has on board a float-free, automatically activated Category 1 406 MHz
EPIRB stowed in a manner so that it will float-free if the vessel sinks.