There is no way I would ever refund money that I had not received. Also, I have had issues with Zelle that makes me want to treat payments like a personal check with a "holding period" before acting.
Here's the most common one: I get a pending inbound. Not sure why the funds sometimes have to wait 1-3 days to clear. If there is a wait, then there are a reasons for that wait that could lead to a rejection of funds. Any Zelle fans able to explain this?
This one only happened once: I get a text showing funds are delivered to my bank account, but I don't see it in my bank account at all. 5 min later I get a text showing it was rejected due to a problem with the sender. If I was the OP and had refunded payment in between those 5 min, I think I would be out the refund.
Just remember guys, do not get in a hurry and make sure your hands are on the money before shipping anything and NEVER buy into the refunding trick. You are in control of the situation unless you get greedy and let your guard down.
Great job listening to your gut.