eMudhra generated multiple weak private keys and included their public counterpart in multiple intermediate certificates. You need to check that all the intermediates are rejected.
DV/OV/EV are "Domain Validated", "Organization Validated" and "Extended Validation" which refer to different levels of checking that the CA should done before issuing a certificate with a particular name in it.
See the lists in https://bugzilla.mozilla.org/show_bug.cgi?id=2083449; I believe that "dv-g3b-" corresponds to the intermediate CA certificate listed as "EM DV TLS CA - G3B"
DV/OV/EV are "Domain Validated", "Organization Validated" and "Extended Validation" which refer to different levels of checking that the CA should done before issuing a certificate with a particular name in it.