Are there any "smart repairer" companies in Switzerland"
They use the heat/reshape/filler techniques.
If diy is an option then get scrap bumpers to practice on and learn the techniques.
Years ago I watched my dad take a dent out of a car roof with an oxy-acetylene torch. Metal roof, low temp flame CAREFULLY played over the area. It worked because the metal had not been too badly deformed and stretched. No need for a combination of heat and cold.
The plastic bumpers can sometimes be done the same way but no naked flame!
From the damage you describe it is worth an attempt as you have paint/lacquer already.
