Re response from Jude. Cannot find previous version 2.9. Changelog on the link you provide simply gives a lightbox of changes but no links. Have tried accessing via wpmudev menu but no success there either. Couldnt even get back to the original post 948560 to give you this response as the links just go to a general list of posts!
If you are saying all the data is still in the database and a future release will reveal it again then I can wait awhile as the affected site is only used three times a year for special events.