First, let me give you an advice... You should check with your hosting provider to get the details if you know how to do that and if they have some kind of customer support (I bet they do). That way, you should be able to gain access to the sites control panel and gain FTP, SQL and other kinds of access ;)
If this does not (or did not) work, then I can try a few "tricks" to help you get the passwords back, but for that I would need at least the password and username of a privileged user of one of those wordpress sites. Without it, it could be possible to get the auth data, but it would be a bit of a hassly, that is, pretty much impossible ;)
Oh and, another advice, I see the others are bidding high, and trust me with this one, if they are such great hackers, why are they on a freelancing site? ;)
Whatever your choice is, I hope you solve that issue of yours.