The teams went to extra time after Taylor Hughson tied the game for Edmonton with just over a minute left to cap a three-goal rally by the Thunder in the third period.
Healey, Nicole Gorda and Mikaeli Cavell scored in regulation for the Pacific region's Thunder (3-0-0).
Sarah Verbeek, Taylor Murphy, Courtney Geisler and Julie Vaillancourt had goals for Ontario's Ice Boltz (2-0-1).
Chloe Sanderson made 26 saves for Edmonton, while at the other end Alexx Ridding stopped 28 shots for North Bay.
Elsewhere, Quebec's LHFDQ Nord battered the Atlantic's Halifax Metro Boston Pizza 8-1 for their second straight win.
Audrey Belzile scored a hat trick for LHFDQ (2-1-0), while Katia Voulinne, Eve-Audrey Picard, Delphine Leonard, Andreanne Carlos and Jade Downie-Landry also scored in the rout.
Breanne Lanceleve's short-handed goal accounted for all of Halifax's (0-3-0) offence.
In the late game, the West's Regina Rebels cruised by the host Fraser Valley Phantom 5-1.
Delaney Frey, Emma Waldenberger, Teah Anderson, Kelsey Bohay and Hannah Heisler scored for the Rebels (2-0-1).
Danika Carter had the lone goal for the Phantom (0-3-0).