I did not make that form required, But I figured it would just be another bit of information that might be helpful. But in most cases I can use time and value to figure it out.

In your case the wallet ID you put in matched the one that I received the bitcoins from.

As you say I would have to get two orders at the same time with the same value to be confused, and if that happened, it would not really matter who's was who's anyway!