Please be advised that there's an update to the clone function, including the functionality to Clone from Site ID.
http://prntscr.com/3x15g8
1. Go to the clone page
2. Get unique ID from the selected site.
3. Click on the Clone Site From ID button then put the unique ID to the field.
Then fill up the other fields the same way just like before. Input FTP details to put the cloned site on the destination server.
Note: Users have to create a new database first on the destination server before clone process is executed. You have to input this new database settings on the database form.