That's weird, I just tried again and it seems to work fine here. Once you step on the button yuou should hear a clicking noise followed by a door opening (if it's the correct button). As SuperJBGAMER has mentioned the correct button is the one that roughly looks like s spider. It is one of the two buttons on the same side as the green exit door is.
see SuperJBGamers video: (Minute 46:38)
You might want to stop the video soon after to avoid spoilers.