SRB,
Negitoro on the attested marksheet.
For Commercial attested 10th and 12th verifications are required.... I believe CBSE records are kept in Jaipur. Might be wrong but check around with your fellow applicants.
The easiest way to do get the info is to contact a flying club and extract it from them. And when I got it done the verification had to be sent to the flying club in a sealed envelope so as to avoid tampering by applicant.
I reckon the next step will be the verification of the verification
Good Luck