Messing around the contents of the fcpbundle in the Finder is always a risky business. Please refrain from it, or do make a complete backup first.
With the library open in FCP, select it in the Browser Sidebar, and do File->Open Library->From Backup...
and choose a recent version but one the predates the crash. Hopefully it will have its structure intact.
Rename the library with a convenient name that lets you know it's the new one, but don't use the long timestamp format of the backups, to avoid confusion.
If the media for the library happened to external, this should be all that is needed, and you should be able to pick up where you left off.
If the media is internal to the library, you will have a bit more work to do. The library recreated from backup will have missing media all over.
NOW, you will need to go inside the original library bundle.
COPY (don't move) the contents of the folders pertaining to each event, to a location outside the library.
Then in FCP, with the new library open, select it, and do File->Relink Files..., select Missing, then Locate, and point to the folder where you have copied your media, then click Relink Files
