DeltAlum, I read your post and Google News'd to see if there was anything else. There sure is, but it seems to make things even murkier. Here's the address for a story on station WCCO's site:
http://wcco.com/topstories/local_story_261192814.html
The quote from a vice president of the university makes it sounds almost like the school was using the incident as an excuse to "do something" to the chapter. Apparently no one has been charged for attacking the victim, and there's no hint that any members of the fraternity took part in the attack.
Very odd. Thanks for giving me the incentive to find an update, even though it raises more questions instead of providing answers.