37CFR1.45(c)
If multiple inventors are named in a nonprovisional application, each named inventor must have made a contribution, individually or jointly, to the subject matter of at least one claim of the application and the application will be considered to be a joint application under 35 U.S.C. 116. If multiple inventors are named in a provisional application, each named inventor must have made a contribution, individually or jointly, to the subject matter disclosed in the provisional application and the provisional application will be considered to be a joint application under 35 U.S.C. 116.
I would recommend getting legal advice, collecting all documents related to the invention, and keeping a diary of all contacts with parties involved.
At some point he will need to sign a declaration (viz. 37CDR 1.45(a)):
Joint inventors must apply for a patent jointly and each must make the required oath or declaration: neither of them alone, nor less than the entire number, can apply for a patent for an invention invented by them jointly, except as provided in § 1.47.
However, the provisions of 37CFR1.47 allow:
If a joint inventor refuses to join in an application for patent or cannot be found or reached after diligent effort, the application may be made by the other inventor on behalf of himself or herself and the nonsigning inventor. The oath or declaration in such an application must be accompanied by a petition including proof of the pertinent facts,...
So, simply refusing to sign the declaration is probably not an option.
The post does not identify the offending university. I think that the aggrieved inventor should check to see what his university policy provides. For example, Stanford University policy can be found on the web at http://rph.stanford.edu/5-1.html. That policy provides that inventions of this sort can be placed in the public domain.
The inventors, acting collectively where there is more than one, are free to place their inventions in the public domain if they believe that would be in the best interest of technology transfer and if doing so is not in violation of the terms of any agreements that supported or related to the work.
Sadly, there does not seem to be a provision for resolving potential conflicts between named inventors nor a policy for determining whether a person should be named as an inventor.