Fifa and the CSA launched investigations and the latter said the 38-year-old was “highly likely” to have been aware of the incident.
In a statement on Wednesday, Priestman said she took responsibility for the actions of her colleagues after a scouting report filed by Lombardi was sent to Mander.
On Thursday, a French court said Lombardi had been given an eight-month suspended jail sentence after pleading guilty to flying a drone in an urban area without a licence.
The following day Canadian Olympic Committee chief executive David Shoemaker said there “appears to be information that could tarnish” Canada’s women’s football triumph from the Tokyo Games.
It followed Canadian media reports that drones had been used at previous tournaments.
Assistant coach Andy Spence will take charge for the remainder of the Games, with the defending Olympic champions’ next game against France on Sunday.
Canada beat New Zealand in their opening game to earn three points but Fifa’s sanction leaves them on minus three in Group A, with games against the host nation and Colombia to come.
The CSA can appeal against the decision before the Court of Arbitration for Sport.
