The location of the Share Preview data depends on the location of the Data folder.
For example, if the data path is E:\inSyncStorage, then the location of the Share Preview is:
Note: This is applicable for inSync On-Premises only.
Administrator has no control over the files and folders deleted by inSync user from inSync Share. Therefore, administrator cannot restore such files. Only inSync Client users have a provision in inSync Web from where they can restore deleted files and folders. The procedure to restore deleted content through inSync Web are described under Restore deleted content section of inSync Client documentation.