Zelle will not contact you and tell you to ship, that's not what Zelle is. How would they know what the money was for? I think you were a victim of a Phishing scam. Go read my post #8 and it gives info about Zelle... Here's Zelle's own site.. where it says only use for close friends....
Zelle® is a fast, safe and easy way to send and receive money with friends, family and others you trust. Look for Zelle® in your banking app to get started.
www.zellepay.com
There is also a scam similar using Wallmart money orders. It sounds exactly what you say happened to your friend.
Just sayin.....