With both sides throwing haymakers at each other in the final minutes at McDonald Jones Stadium on Friday night, Socceroo midfielder Anthony Caceres teed up Vickery to seal the victory.
"I knew there wasn't much time left and that was a make-or-break moment for the game," Vickery told broadcaster Paramount.
But the win was controversial, with a shoving match breaking out after the final whistle as the incensed Jets appealed for a free kick against Harrison Sawyer in the build-up.
"That is every day of the week a foul," Newcastle coach Mark Milligan told Paramount.
"We got told that it can't be checked (by VAR) because (the referee) didn't give the foul and it was too far back."
The Bulls, who move up into fourth, had only scored seven goals in nine games heading into Friday, amid reports that they are set to sign Socceroo striker Mitch Duke in the January window.
Japanese side Machida Zelvia announced on Christmas Day that Duke would complete a permanent move to Campbelltown.
The Bulls, who lost Korean forward Ji Dong-won to injury earlier in the week, are yet to confirm the deal, but Paramount also reported the 34-year-old's impending arrival.
Playing their third game in eight days amid domestic and Asian commitments, Harry Politidis suffered an early ankle injury to add more injury woes for the visitors, but that didn't stop them taking the lead 15 minutes in when Liam Rose set up Bernardo Oliveira to poke home.
The hosts, who lost Daniel Wilmering in the warm-up, equalised in the 42nd minute via an unstoppable Eli Adams free kick, but fell behind again moments later when James Delianov knocked a cross straight into Dean Bosnjak's thigh.
Clayton Taylor restored parity three minutes into the second half, but Bosnjak's second made it 3-2 two minutes later.
Sawyer's 68th-minute tap-in to make it 4-2 was answered by Xavier Bertoncello in the 75th minute, and Ben Gibson thought he'd rescued the Jets a point in the 83rd minute, only for Vickery to have the final word.
"It was a good spectacle," Sawyer, who now leads the league with five goals, told Paramount.
"Merry Christmas."
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