The ref from the first leg who missed the tyre warming should be disciplined, the Poole leg is not so clear cut, riders leaving the track is normally black and white and is followed by an exclusion light, saw it happen all the time in the late 80s before Arena had a safety fence installed.
Thing is if Cook had sat behind Pickering it still would have been a Poole win, its not like the pass enabled the win.
I think its one of those things that a decision has to be made in real time and thus conclusive, once a heat is completed other than a tie for position on the line, the race should be called.
Anything that comes to light afterwards should result in the ref being disciplined and banned for a period of time and certainly losing the right to ref any higher prestige meetings, they are paid to do the job, hit them in the pocket.