We have not specifically done this yet for Spectrum 10 and CABI4.1, but it has worked in the past for installations that "required" a RHEL release.
You should be able to edit the /etc/redhat-release
Suggestion, copy off the original redhat-release to something else. Then after you do your install, put the original back. We always have our systems with their real redhat-release file and only make this change during installations.
example, for
CentOS 5.8 the RHEL equivalent would be: "Red Hat Enterprise Linux Server release 5.8 (Tikanga)"
CentOS 6.5 the RHEL equivalent would be: "Red Hat Enterprise Linux Server release 6.5 (Santiago)"
CentOS 7.0 the RHEL equivalent would be: "Red Hat Enterprise Linux Server release 7.0 (Maipo)"