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The employee made a mistake. Airport lounge access is offered with the American Express Platinum charge card, and does not apply to any other card which happens to be platinum color or include the word "platinum" in its name. This is the card:
https://www212.americanexpress.com/d...00cef4ad94RCRD
Just to clarify a little further, the Canadian Platinum Card linked above provides access to the "Pearson Priority Lane" and grants access to select Canadian airport lounges run by these entities:
Participating Canadian lounges are operated and managed by Plaza PremiumSM Lounges, Servisair Executive Lounges, and Aéroport international Jean-Lesage de Québec.
The AeroplanPlus Platinum Card also provides access to the "Pearson Priority Lane" but not the lounges I just mentioned. Instead, it gets you into the Air Canada Maple Leaf Lounge if you're ticketed with Air Canada.