Duplicate Avoidance Not Working or Unclear

[Obscure2020]

The latest version of the README says the following:

Prefix this token with an ! to ensure no duplicate modules.

I tried to make use of this, as shown here:

However, this didn't work.
The bomb that resulted from these settings had the requested types and numbers of modules, but contained both a duplicate set of buttons and a duplicate set of passwords!
Here's the front of the bomb:

And here's the back:

(Disregard nonstandard bomb coloration, that's the work of a separate mod.)

This means one of the following is true:

1. The new Duplicate Avoidance system as outlined in the README is a lie and must be removed from the README.
2. The new Duplicate Avoidance system as outlined in the README is not functioning and must be fixed.
3. The new Duplicate Avoidance system is working, I just typed it wrong. If this one is the case, the README must be updated to restate more clearly WHERE you're supposed to put the !.