Asking on the behalf of my friendRegistered mail is the worst option for in and to Canada.
If you have sent the application from outside Canada, Canada Post would be the one to accept international registered mail. Registered mail is basically free mail, they are barely making anything off it. If you have been checking the track and trace you might have seen there is no updates if it has reached Canada or if it was somewhere within Canada. Despite the fact you have paid for track and trace its a free service to them to update your track and trace.
On top of this, registered mail is not really a priority in Canada. They can wait with registered mail as much as they like for them to finally reach their destination. Your package can take 3 weeks, 1 month, 2 months or longer.
He checked on "On-line services" tool to see his status and this is what he found on point 5 (after point 4 which is your medical result have been received)
" We sent you a letter on July 15, 2021
But he never received any letter so my question is what that 5th point is all about ?