^yes, but these units were from mumbai and not flown from j&k,
that's some logic ! I'm sure the units/personnel are not anchored to one location as you seem to think.
SF units would be rotated and would probably retain most of the fatigues etc. may be the personnel were just back from K or were preparing to go there ! who knows ?
all I do know is that the gun has been IDed as the SVDS, one knowledgeable person has claimed that MARCOS is the only force using it.
the fact that the SVDS is a highly compact SF oriented product lends credence to this theory.
the IA SF units which do use snipers do not specialise in urban HR operations(they have completely different roles) and none were reported to be present in mumbai.
also, regular IA units use the the fixed stock dragunov and the IMI galatz in the sniper role.
all in all, I'm convinced that the sniper is from MARCOS.