Relieving Date Overlap Issue

Hi Seniors,

One of my fri is having employer date overlapp issue, he worked with X organisation(first company) for 15 months, x company is a small consultancy, outsourced to top most service based company. He got placed in biggest banking MNC Y company, from X company he got relieved on Dec-2-2013, where as DOJ in Y company is Nov-25-2013. He worked with Y company without any problems for 20 months. Now he started working with Z company for 8 months without any discrepancies.

Now he got oppurtunity to work with worlds biggest product based company, company questioned abt the dates overlapping between X and Y company i.e.., DEC-2-2013 relieved, Nov-25-2013 joined, overlap of 7 days.

Note:- X company client relieved him on Nov-24 without any records, only the client manager knows the relieving of him. Already approached X company for relieving date change but manager is not agreeing for the amendments.

Please need your valuable suggestions to get the issue sorted out.

Thanks in advance.

Regards
Sunil

May be X company orally relieved him on 23rd Nov., but due to non-availability of signing authority, it was offically issued only on 2nd Dec

Seniors,
Orally he got relieved on Nov-24, whereas in papers date mentioned is Dec-2nd. New company is not allowing him to join the company without clean and clear relieving papers.
Need your valuable inputs on how to approach the X company consultancy manager to get the issue sorted out.
Tons of thanks!!
Regards
Sunil