H1B Dropbox in Canada while staying in the US

Hello,

I am currently in USA but I do hold Canadian PR so I am able to get a Dropbox appointment for H1B stamping at the same consulate where I got my previous stamp in canada (Toronto).

Can I mail my passport and documents from US and have my passport be picked up by a friend (once stamped) and have him mail back my passport to USA?

I do not have a luxury of staying in canada for 4-6 weeks while Dropbox application is being processed.

Thank you if anyone can provide any insight on this.