Well, in fact, her assertions about what she agreed to and why are what is relevant.
She states that she agreed as a result of the representation made to her by the Union that there would be significant media coverage of the event and that the level of media coverage would be hers to decide.
They specifically stated that the event could be recorded for broadcast on Youtube and in fact, it was so recorded.
Apparently, all concerned signed a waiver to confirm they were happy with that. That would obviously include Mr Shedd.
Even if he did not agree or if, as seems likely, the offer of media coverage at the level the speaker desires was made to all the panellists - that just means that the Union made representations it might not be able to fulfill.
Did you read her transcript? What she said was hardly “off on a complete tangent”. It was all explicitly linked to the topic of the panel.
Yes, the transcript is online - put there by Heather Marsh.
The comments from Mr Shedd are fairly obviously removed and summarised given his insistence that he does not want his comments and involvement in the panel published.
No, it doesn’t. See above.
There seems to be no question that the Union is entitled to publish the video if it chooses to. At least the Union does not appear to have argued that it is prevented from doing so. If it were able to make that argument, you would expect it do so since “We can’t publish for legal reasons” makes a far better PR response than “We don’t have to and we’re not going to, so there.”