You're NOT going to get shot down. When is the last time a nation knowingly shot down a civil airliner ?
You're likely NOT in a weapons engagement zone to begin with for chinese SAMs.
The chinese don't fly continuous armed CAPs looking for errant civil airliners. AND intercepts take significant resources and time.
AND you're talking to someone who can talk to others. Cannot to them means don't want to.
Do what you need to do declaring what you need to declare. The worst thing that will likely happen is you have to explain what you did later. This is pretty easy to do when it involves storms.