"second-source can do the same for the cloud"
I have my doubts on that point.
The way I see market conditions these days, having an open-source based second-source supplier that becomes successful is going to entail two things :
1) open-source developers are going to attack the company to get what they consider is their "fair share" of the spoils, and
2) AWS, Azure or any other multi-billion behemoth is going to lavish the company board in boatloads of billions to buy them out, and they will fold
So, short or medium term, any successful open-source-based company with big government contracts is going to disappear, either because of lawsuits, or because of bagfulls of money.
Return to step one.