Question 1: why do we have these 8 minutes

There are a number of questions that need to be addressed. One is why were these eight minutes chosen for release?

My guess is that Grewal chose these eight minutes because his initial concern was to prove that it had been the Liberals who had approached him, not vice versa. In this section of the tape he manages to slip into the conversation twice that this was the case. (This is not clear evidence as to who really did make the initial approach, since Grewal knows he is taping his own conversation and could have chosen to lie on his own tape.) It was only once the tape was public that someone pointed out that this may fall afoul of the criminal code provisions about 'selling' offices.