The GitLab EE source is publicly viewable, but its license is not open source. See https://about.gitlab.com/2015/05/22/gitlab-7-11-released/.
[1] I.e. a licensing model based on GPL and selling services that Red Hat uses for RHEL, instead of a licensing model like they, and a minority of the "open source" companies, use.
Anyway, maybe you could be a bit more specific about the problem you see with our model, I would love to get specific. Also see https://about.gitlab.com/about/#stewardship
BTW I presume RedHat choose a GPL license for RHEL because they didn't have a choice due to the GPL license on Linux.
We tried charging only for support but now that we have the Omnibus packages it is rare for users to need support (and we like it that way).