"If you fly in Canada than I imagine you have a Canadian passport"
Canada does not require Cdns to have a passport to enter canada, neither by air or land.
US requires Cdns have a passport for entering US, by air.
So a Cdn could fly to canada without a valid passport. You can get a passport in 24 hours, if you pay the premium, and have a confirmed ticket in your hand. I would give myself 3 days to be safe.
Then fly back, getting new TN.
Or, sinply apply for TN by mail, or drive to the border, without renewing passport, and get the PP renewed when it is more convenient, and when the backlog has died down.