The information received through the RTI Act, 2005 in India may well be used as authentic data for research purpose since this entails the official version of the information from the legitimate custodian under law. Further other than this one may not have alternate arrangement to receive desired information as such.
Various authors use the data/information received from the legitimate custodian of the source of information. In government sector, due to various reasons, sometime authorities hesitate to share such information even to researches.
RTI Act in India is a newly emerged legal tool by which one may may get such information by the authorities which otherwise might have denied to share.
Hence I find no reason for you doubt on the information received under RTI to use for research purpose. The data/info so received is perfectly authenticated and genuine for referencing.