I think you need to study thumbs before you enter this conversation. At first glance that does indeed look like the pinky finger. This is simply gleamed by the way the finger is pertruding straight up and the way the arm is even drawn, suggests we are looking at the back of the arm.
Come on bro are you really telling me the hand on the LEFT is wrong to you? "Study thumbs" lol really? I have one an I know that, that thumb is perfectly fine. Your being weird about thumbs....the fact that the thumb is lower than the pinky makes it clear that its a thumb. Also the round palmy part n.n