No, multiple won’t (or the conference will be cancelled)

'cancel':10 'confer':7 'multipl':2 'won':3

 (Manifold's planned September conference in Berkeley) lists Scott Alexander, Aella, Destiny, and Robert Miles ("...and more") under "Speakers & Guests of Honor." [UPDATE: It no longer lists Scott.] Will each of them actually show up?

For this market, a virtual appearance counts as long as it's live (not pre-recorded).

I hope to attend the conference to verify, but otherwise I'll get info from people who were there.

In other words, resolves like the embedded market, but without the "as some part of the official program" part. So any kind of appearance during the conference would count. 

General policy for my markets: In the rare event of a conflict between my resolution criteria and the agreed-upon common-sense spirit of the market, I may resolve it according to the market's spirit or N/A, probably after discussion.   