In this game, I think my opponent is scoring the board wrong. Go 9x9 (troydaniels vs. Honor.j)

I think that a5, b5 and b4 should also be mine, giving me an additional 3 points and changing a 1.5 point loss (as currently scored) into a 1.5 point win. Am I misunderstanding the rules, misreading how the board is shown, or is it scored correctly?

I am new to playing Go, so I could easily be mistaken.