I have emptied both trash-sites. Is there a way to continue playing or have I won/lost?
Good news first. You are not stuck, and you do not have to wait for the update.
Open the Machine Tree. You have three skills sitting there that you can already afford and have not taken, and the one that matters is Staffing at 225. Take it, and Greenhaven opens for nothing straight away. Stripping the Wastelands bare is meant to open it for free, and your empty tips are what pays for that. If you still have trash left in a tip, it is not free yet and Greenhaven wants 490, so keep burning for a bit.
Now the part that is my fault. Greenhaven sits behind Staffing on the tree, and the free route for a bare map only ever removed the price. It never removed the prerequisite. So that hex has been sitting there saying FREE at you and refusing to be clicked, which is a horrible thing to show somebody. I would have filed the same report.
Two things are changing for the next build. The bare map route will clear the prerequisite as well as the cost, and Greenhaven will open by itself rather than waiting to be found. Nobody looking at an empty map should have to guess that a tech tree is the answer.
Thanks for reporting it. Selling everything instead of burning it is a perfectly fair way to play and I had never once tested it