since everything newer than RHEL 6.4 is not supported by HP, an unsupported solution to this issue is, to copy the isolinux.bin from a RHEL6.7 ISO to the /opt/omni/bin/drim/linux-XXX/cdboot/ directory on the media creation host.
- /opt../linux-amd64/cdboot/isolinux.bin
- linux-amdx86/cdboot/isolinux.bin
THIS IS NOT SUPPORTED
After exchanging the isolinux.bin, the recovery.iso will work correctly.