I see they got their first two AW139s 18 months ago:
Korea Coast Guard Takes Delivery Of Two AW139 Helicopters | INTERNATIONAL AVIATION NEWS
Korea Coast Guard Orders Another AW139 Helicopter | Vertical - Helicopter News
The photos in the press don't show the port side were the HRSmith ADELT would be.
However this photo suggests no ADELT:
Photos: AgustaWestland AW-139 Aircraft Pictures | Airliners.net
ADELTS may have a chequered history but there is also a long history of fixed ELTs failing on impact. The Cougar S-92 being one of the most recent cases.
The Caladonian/BHL ADELT on the PHI S-76C that had a bird strike in the GOM in Jan 2009 did work even after an accident that killed all but one on board.
Sat tracking is great if you actually monitor the data. Here is one case at Air Logistics in the GOM where false confidence in the data, inadequate flight following software and poor procedures may have delayed a rescue, fatally:
DFW08FA053