The keyboard layout was changed a while back, so the current keyboards don't have the Dashboard key anymore.
But by default Dashboard should be visible in Mission Control. See that you have the option 'System Preferences -> Mission Control -> Show Dashboard as a Space' enabled. Then you should be able to access it either with the Mission Control Key, a three finger swipe upwards (opens Mission Control) or three finger swipe to the right (changes Spaces to the left).
That being said, I don't seem to be able to get Dashboard show up as a space, or even open at all for some reason, but if you are able to open it from /Applications, you should be able to access it with the aforementioned ways.