Al Queda was probably not involved directly. It merely provided the assassins. I suspect it was a dissident Indian group and/or a Paki group that used them. I do not believe, given the available info, that Paki government was involved.
You’re right — AlQ would be indirectly involved, but they were involved int he planning and training that is there, no other group is capable of this. The assasins however, were from Pakistan, that’s pretty much proven. And quite definitely recruited by Lashkar e Toiba. They were not Indians and not even from Pakistan occupied Kashmir — they seem to have been from Pakistani punjab