Canada has already apologized.
The federal government was responsible for setting up the schools and removing children from their families to be placed there. The schools themselves were operated by various churches, primarily Anglican, Catholic and Presbyterian, and it's what those churches' employees did to the children under the management of their particular church that the apology is for. The Canadian branches of each of those churches are paying reparations to the victims and participating in the reconciliation process.
I can assure you that the Pope is well-aware that this request is coming and isn't finding out through the media.