While one can appreciate Mr. Mahesh Nair's response, his making a sweeping remark that what the fellow HR Member/Professionals say is 'void' is condoned, and I as a professional stoutly protest this, even if this is a mistake. It would have been nice for him to have made his point, and to also have gone through the query (the candidate in question is a fresher, so experience and a reference from the HR of the earlier company doesn't arise at all).
While companies claim to have been attained CMM Level 5 they use it for publicity, they could have multiple center/branches and various practices, they could have been on the basis of a center or practice. In this case this is a fresher and the company in question is TCS, (some center/s could be assessed at Level 5 - on CMM, hence it would be interesting to see if the candidate has a rejection on BGV from the assessed at Level 5 - on CMM.)
TCS News & Events: Press Release : TCS sets new benchmark in Quality; First software firm to be assessed at Level 5 enterprise-wide in software services and development
Coming to the aspect of rectification, or seeking redressing/addressing the issue costs nothing, even if it should mean a rejection. All of us know, there are a lot of professionals who would find it difficult to admit they made a mistake, who knows it might cost them their job, so why will they put their neck on the noose. It's easier therefore to say, we found there is nothing incorrect in the BGV and so we reject.
Trial has to be made irrespective of the result.