Vegas appeared to go ahead 5-4 at 10:08 on a Stone shot from the slot, but Vancouver challenged successfully for game stoppage because the puck hit a lens in the camera hole in the corner 14 seconds earlier.
Pietrangelo finished off a passing play from Stone and Chandler Stephenson just over four minutes later with a shot between Demko's pads to make it 5-4.
"A lot of emotions, obviously we score and then it gets taken back, but I'll tell you what, it's not easy to win on the road and you've got to give credit to our group," Pietrangelo said. "We were resilient no matter what happened. I don't think we wavered after that disallowed goal, got right back at it."
Kuzmenko put the Canucks ahead 1-0 at 11:48 of the second period by finishing off a pass from Brock Boeser, who extended his point streak to seven games (eight points; two goals, six assists).
Eichel had two assists 49 seconds apart to put Vegas ahead and extend his point streak to four games (one goal, four assists). Stone tipped in Eichel's point shot at 14:52 of the second to tie it 1-1, and Eichel's shot from the top of the right face-off circle deflected in off Carrier at the side of the crease at 15:41 to give the Golden Knights a 2-1 lead.
"There's definitely some things we'd like to clean up, but you can't argue when we're down two goals in the third period and we find a way to win and get two points and in regulation," Eichel said.
NOTES: Golden Knights forward Jonathan Marchessault had one assist while playing 16:57 in his 500th NHL game. … Vegas defenseman Alec Martinez had two assists, three blocked shots was plus-4 in 22:17 of ice time. … Canucks defenseman Quinn Hughes had two assists and leads them with 18 assists this season.