The certificates generated using SDK (
registerUser.js) are stored inside
wallet/ and you will see three files: one public key, one private key and one file with the name (admin or user1). Inside which you will see the PEM of that certificate.
If you wish to make it readable like the one shown in my article, you can use openssl tools.
openssl x509 -noout -text -in <cert_in_pem>