Site crashed from plugin

Please help - my host sent me this:
You WordPress site crashed about 6pm.

PHP and MySQL are both working.
http://rugbydudefitness.com/rdf-phpinfo.php

Other WordPress sites on the same server (same PHP and MySQL) are working.
http://shatterglassstudios.com/

I have spent about 30 minutes and managed to get/find the following PHP error:

Fatal error: Cannot redeclare class FacebookApiException in
C:\HostingSpaces\RDF\rugbydudefitness.com\wwwroot\wp-content\plugins\wpmu-dev-facebook\lib\external\base_facebook.php on line 107

My best guess is that this plugin uses the Facebook API and either has a bug or is not properly catching errors. Maybe something has changed on the FB API or the FB services are down or … something. But this error took down the whole RDF WordPress site.
If you know what plugin that is, can you please open a support ticket with the developer right away? Forward him this email, he can use the PHP Info (linked above) to get a good idea as to the hosting configuration.
Since the error is being caused by the plugin and may be in response to any unexpected in dealing with the FB API, it may suddenly start working again. But so far the site has been down since 6:05pm.
Thanks – Jeremy