Yes, but making the “Good” option the biggest one would separate it from the group, the opposite of what we are trying to do 
The only way to create a clear distinction from the three pass vs the one fail button on a small screen that I feel could work is this.
Edit: plus, the good button is in the middle of the screen, which makes it accessible from both hands. Maybe I could try a mock up with the “Good” a bit bigger than the other two but in the same place? 
Edit 2: here it is.
