soft copy is available online through your account itself, it's a sample online report showing the result you've got rather than a soft copy of the actual report you'll get itself..
meaning, you won't get the certificate number you're expecting.. though the certificate number is the reference number that you get on creating your WES account (after payment) initially, post fixed with some characters (like if reference no. was 1234567 then certificate no. could be 1234567/doc)
so I guess till the time you get hard copy, you can enter your result (equivalent) as per online report and the reference number itself as certificate no, and later update the complete no. when you get hard copy... my view though