Dual Chinese/British travelling from China to Europe via third country - What non EU countries are suitable?

I am British my wife is Chinese. Our kids hold passports for both countries.

Last year we used method three from here to travel to visit family in the UK. Dual Nationality Thread

Last year we managed to get visas for France for my wife and children in their Chinese passports and also a UK visa for my wife.

We traveled out of China on their Chinese passports (this is the only way, the Chinese see the kids as Chinese) and arrived in France. Then we left France and flew to the UK, my wife used her Chinese passport to travel and my children used their British passports to exit France and to arrive in the UK.

This year we tried the same process. My wife was granted a French visa however the kids were not, the reason being that they do not believe the itinerary that was supplied with the application. The three applications were identical for the whole family - so we are currently trying to appeal this decision.

I am worried that making a new application for an EU visa while we are still appealing the first decision may not be viewed in a good light.

We are looking for alternatives arrangements to get to the UK.

What countries have others successfully traveled via en route to the UK?

Dubai does look like an option - but I do not know how strict they are with the passport control. If a Chinese passport is used to enter the country, will they take issue with a UK passport being used to exit the country?