When trying to salvage it, I've tried both commands both of you suggested, but it tells me command not found:
Bitcoin-Qt.app -salvagewallet
-bash: Bitcoin-Qt.app: command not found
Look at my message -- that command won't work, you want the following command:
open /Applications/Bitcoin-Qt.app --args -salvagewallet
This is because in OS X, applications are actually folders. Bitcoin-Qt.app isn't an executable, the executable itself is a few folders in, I don't remember the exact structure off the top of my head. The `open` command will look at it from OS X's perspective, and do what you want.