Vidal's 81st-minute header after a pass from substitute Alexis Sanchez gave the South American champion a Group B win which was anything but routine, before another goal was decided by video review.
Slovenian referee Damir Skomina initially awarded it but then, more than minute later, he suddenly reversed the decision on the advice of the VAR, Clement Turpin of France.
That wasn't the first time the VAR system came into play in the match, either.
The Confederations Cup is always an interesting tournament for some of the fascinating matchups it brings about, like 2017 AFCON winners Cameroon taking on 2015 Copa America champions Chile.
Chile, who were by far the better in the opening stages, were left frustrated and struggled to regain consistency after the break.
Stay tuned for more live goal updates of the FIFA Confederations 2017 match Cameroon vs Chile.
Sanchez charged through the Chilean defense, but saw his shot saved by Ondoa, only for Vargas to score the rebound.
La Roja squandered another golden chance in the 40th minute when Vargas was played through on goal, however the striker blazed horribly over the crossbar.
Cameroon could also have argued they should have had a referral in the first half when Vincent Aboubakar was harshly adjudged to have pulled back Vidal as Michael Ngadjui headed in a free-kick.