Are all the WM2014 videos up?
If so, is the reason some appear to be missing possibly the existence of those several-hour videos with names such as "0bbca578 b967 4a27 9de2 3bafb500cc50" and "4ca853b7 cafa 436d 8031 70499c143cd1"?
https://www.youtube.com/user/WikimaniaLondon/videos
Who has access to the account and can rename them to reflect the name of the programme session they are recordings of?
Thanks,
A.