Firstly, Call details will not be given to anyone and everyone, even though you are involved in a case, etc.
When court itself did not pass the order, then Police will not even consider it.
Lastly, even if you succeed in getting the order, No telecom company stores Call and SMS details for 7 years. Maximum it will be stored only for 3 years.
Had you informed the mobile company about the case running with the court order, then they would have stored it.
Having said that, I would suggest you not to rely on Call Details and other Records. Instead, get a good Criminal Advocate who can cross examine well and get the truth out of the Accused.
Understand that case can be proved even without any documentary evidence. And the case is built right from the stage of Cross Examination.