In my opinion OpenStack is an iffy example for your Multi-Vendor archetype, as it shares a lot in common with the Wide Open Archetype as well. In particular, its technical governance is democratically elected (not appointed) by all active individual participants (not their employers). The community, and particularly its leadership, recognizes that unaffiliated contributors are a significant asset necessary to ongoing/future success and tries to make sure that their contributions are valued equally. It is true that a majority of the overall development activity is being directly funded by hundreds of different organizations, but among its subprojects there are many where the balance of contributions from people not paid to work on OpenStack is significant.
In a comment on the OTS Blog, Jeremy Stanley says: