Old Bank Statement Request Citibank Savings BDO Acquisition

Recently Citibank Savings Philippines was acquired by BDO last August 2014. I have an old payroll account (probably closed sometime around 2012 due to dormancy). I need my old statements from Nov 2011 to Feb 2012 due to an ongoing issue I have with an individual regarding their debt. Due to the acquisition they have pingponged me back and forth between BDO & Citibank and both saying they do not have access to my old records anymore. BDO is saying they only acquired ACTIVE clients so any accounts closed prior to Aug 2014 will not be part of the acquired client accounts. That may be true. Citibank is saying they do not have access to the old legal entity as it was already bought by BDO. Who is responsible for the old records and how can I oblige them to provide this to me? I read that there is a requirement for bank to retain records up to 5 years after account closure. Since this is a unique situation, what are my rights to oblige Citibank to provide me these old statements and how can I push them to accommodate this request? Would appreciate your advise on this.