If the your flight school is Part 141 approved, just get a copy of the certificate issued by the FAA.
I requested our Chief Pilot to sign it as an attestation but he refused to sign the FAA certificate since he isn't an approved FAA authority to do so.
I submitted the copy of the certificate without attestation and had no issues with it.
You can try and call the DGCA and speak to someone in the Training & Licensing Department. If you're lucky, they'll help you out.
All the best.