This Q Kaur & all other participants is quite simple to reply for a newcomer like me...
Ask the participant/ certified person to. Go to URL
The student can use his S user ID(same as the participant ID) to Logon then go to > My Training > Qualification
(Here u will find the module the person is certified in and also the pass date)
The person can then take a screen shot a keep it as a confirmation of being certified.
Since training.sap.com is '"very official & legal/legit" this should suffice !!
Also the authorized SAP education partner can send an email on request to confirm the same.
Hope clears all dilema, remember u heard first from Som!!!