Subsequent to the blog you referenced that I posted in June 2018, I have since written a new blog that utilizes the Graph APIs which essentially achieves the same desired results.
The later approach using the Graph APIs is considered a far better & Microsoft recommended technique over the technique using the SharePoint RenderListDataAsStream REST API I had in my earlier blog (in June) described.
Additionally in my latest blog(s) I have equally shared the demo solutions 😉.
My understanding wrt the lisensing is that for each (standard) user license your organization has ('...'), your organization "as a whole" is a collectively lisensed for 2000 x '...' lisenses. The total number of Flow licenses your organization has is a collective total, irrespective as to whether one app runs a Flow 30k times or for matter one user runs a Flow 30k times.
Thus if your in your organization you had 10k users, the collective number of Flow runs for your organization would be 20m (10k x 2000).
By all means correct me if I'm wrong though as I don't speak for Microsoft LOL