Void Starnberg water temperature record in June?

The provided source shows the temperature in a graph with a red

"maximum" line. This line however, is not the Max referred to in the market.

The Maximum for June is nowhere to be found in the source chosen for resolution, which makes this a completely unfair information arbitrage for whoever created the market and knows the June maximum temperature.

To prevent exploitative behaviour like this in the future, this market should be voided, and all losses/gains should be given back.

This is the graph mentioned: