Earlier quoted context omitted.
The RPM SPEC file in that repo will have a pointer to the actual upstream sources for the package. This is a typical scenario -- they are not re-hosting all of the sources to build a Linux distro, just the build steps needed to pull, patch, and build upstream sources.
So where do I actually get this upstream (RHEL8) source of say dracut? Because I was reacting to the comment "Red Hat publishes it's sources on https://git.centos.org . Those are then used to build CentOS Linux packages."
This is the regex used in the watch file for Debian to fetch new upstream tarballs: http://www.kernel.org/pub/linux/utils/boot/dracut/dracut-([\...