Apparently the header parameter is not necessary
On CC7:
LC_ALL=C /usr/bin/openssl ocsp -no_nonce -issuer /etc/pki/tls/certs/CERN_Certification_Authority.pem -cert /etc/pki/tls/certs/juarez7.cern.ch.pem -url http://ocsp.cern.ch/ocsp/ -header Host "ocsp.cern.ch"
On C8:
LC_ALL=C /usr/bin/openssl ocsp -no_nonce -issuer /etc/pki/tls/certs/CERN_Certification_Authority.pem -cert /etc/pki/tls/certs/juarez8.cern.ch.pem -url http://ocsp.cern.ch/ocsp/ -header Host="ocsp.cern.ch"
Note the Key=value part. On CC7 the help does not even show this parameter. Anyway, it does not seem to be relevant.
Moral support needed.