Moncton held 2-0 and 2-1 period leads.
Daniil Kuzmin scored an empty net goal with 39 seconds left before Evan Gallant made it 4-2 20 seconds later.
Mika Cyr and Anderson MacDonald also scored for the host Wildcats.
Defenceman Taylor Egan scored a power-play goal for Charlottetown. Saku Vesterinen, Nikita Alexandrov and Antoine Leblanc had helpers for the Isles.
Former Islanders goalie Mark Grametbauer started for Moncton and stopped all eight shots he faced in 29:24. Philippe Gaudreault allowed two goals on 13 shots the rest of the way.
Marc-Antoine DuFour allowed three goals on 32 shots in the loss.
Charlottetown was 1-for-6 on the power play and killed all six of Moncton’s attempt with the man advantage. The Islanders held a 31-30 advantage in the faceoff circle with the Wildcats credited for one more hit.
The Islanders dressed a more experienced lineup this time around after losing 4-2 to Moncton Wednesday in Cornwall.
Charlottetown will play at Acadie-Bathurst tonight at 7 p.m.
