Ok guys and gals,
I am trying to track down this issue and to the BEST of my knowledge here is how I think it happens.
A player starts playing Dungeon Quest on an older patch version and have an older version of Google Play Games Services. They then UPDATE their game along with their Google Play Games Services app (through the google play store).
Now when they complete a feat for the first time in the game they DO NOT get the achievement credit in Google Play games (or game center for that matter).
Can anyone chime in here and help me track down this issue (I cannot reproduce it)