Fake corruption charges

Hello This is regarding My dad.He has been in Delhi govt service (F&S) for past 30+ years,last year while on raid along with two more fellow officers,he was caught in fake corruption case,The complainant filed an FIR stating that One of the officer was recorded on camera collecting bribe,in his defense the officer caught, said other two members(my Dad and another one officer) are also involved (there is no video evidence showing my dad demanding or taking any money).So as per complaints, all three were suspended.(FIR not issued to my DAD). My Dad has been suspended for last 8 months,even after all clean records ,departmental enquirers ,he hasn't been stated back saying the report is yet to come,now officials(Vigilance) ares saying FIR will issued first against him as per Delhi Govt CM's Instructions,he will be jailed,then in court it will be considered whether My dad is guilty or not. so I want to enquire what we can do for fake case like this,My dad is a clean government officer who is totally against corruption,whether his previous 30 years of clean service record will not be considered,just because someone took his name will he be also involved,there so evidence against My dad. What can we do earn back his job and respect,and put shame to fake complainants like these and the department for not trusting its employees but the fake complainant. to which departments can we take our case? and legally what help can we take?? Any Help ?