Tom, thanks for the comment. Leaving aside the question of which defendants were agencies or instrumentalities of the Chinese state and which were not, the likeliest reason for seeking alternative service, it seems to me, is that Missouri knew that the Chinese government would not execute a request for service under the Service Convention. For non-governmental defendants, a refusal to execute the request leaves service by alternate means under FRCP 4(f)(3) as the only available alternative. For governmental defendants, Missouri could (indeed would have had to) serve process by letters rogatory through the diplomatic channel, but that takes a long time.

I think the main reason there hasn’t been much litigation against the Chinese government isn’t related to service of process. It’s just pretty obvious that foreign sovereign immunity will apply given the nature of the allegations.