Yes, I'm aware of that documentary: he is/was definitely an MKI driver. The Indians on some forums are however claiming that he went on to fly Mig 21s after being on the MKI. I dont know how much sense that makes? In view of the eyewitness accounts it is looking increasingly likely that he was in a two seat aircraft when shot down. A big big pointer towards a flanker.
Also, it is possible that the footage of the crash from Kashmir is of a helicopter. The second aircraft that was shot down may possibly have crashed at some other remote location. The region is highly mountainous and sparsely populated. It is quite possible for the Indians to seal off access to a crash site in those remote mountains. They are not saying a word, either.
That alone is quite possible. However, it is far less possible that India sent MiG-21s only to intercept a PAF formation. There is also the eyewitness account of two parachutes at the same time and the claims of 3 pilots lost but only 2 aircraft. MiG-21s are single seaters.
Finally there's also the crash site pic which clearly shows a twin engine plane. Some Indians are now claiming it to be a MiG-29, which is quite possible. But Indian media also indicated that Su30MKI was operating in the area before suddenly taking down that claim. There have been no media claims of MiG-29 in the area. However, that doesn't mean there couldn't have been one.