I've discovered multiple instances of two Avatar awards for a single Steam Achievement. I believe this to be intended.

Some examples:

 and

 and

etc.

​

makoto wrote:
Hello there, 
Some achievement ranks have several linked avatars, which is deliberate indeed. But thank you for your feedback!

Thx wasn't aware but it's nice to know that it isn't a failed and thx for the achievement it's really a nice thing to have. Love collecting ;D