What is the right thing to do in this situation?

You answered correctly by choosing to wait before the junction.

In this situation, a traffic officer is controlling the intersection. According to German traffic rules, the instructions of a traffic officer take precedence over traffic lights and signs. The officer is standing with his arms extended sideways, which means you must stop and wait. You are not allowed to proceed or turn right without waiting until the officer signals you to go.

Even though your turn signal is on, you must wait before the junction until the officer explicitly permits you to proceed. Ignoring the officer's signal can lead to dangerous situations and penalties.

So, the rule here is: always obey the traffic officer's signals first, and wait if they indicate you to stop, regardless of the traffic light or your intended turn. This ensures safety and proper traffic flow.