Hopefully someone with a Delano can talk about their experiences with this model.
It sounds like you have a mix of Mercedes issues and Thor issues. Not sure if the water pump problem was for engine cooling or the fresh water tank but the ignition and O2 sensor issues are Mercedes problems. The flooring, blinds and water issues is all on on Thor. The fridge will be handled by Thor even though they don't make it. Tank sensors are notably unreliable in some cases for many different reasons.
It is unfortunate that you had some veryl bad luck having issues with three different manufacturers, which is compounding your frustrations.
I'm not sure what dealer you are using.... but for the Thor issues, I would call Thor and ask for an appointment at the Thor Factory Service Center in Wakarusa. They are the best and will fix everything to your satisfaction and better than the day it rolled off the assembly line.
You are stuck taking it to Mercedes for engine / chassis related issues.
__________________
|