I view this in a positive light. No wiggle room for Kim Jung Un......
If Xi and Trump are on the same page, Kim, if he resists, could be squashed like a bug!
I view this in a positive light as well. China must be included. The US is there because we support South Korea, China should be there because they support North Korea, and more importantly as a reminder to Kim that China (his largest benefactor and sole reason for his survival) supports the upcoming negotiations.
If it is now in the press that China may participate, it was already decided, probably during Pompeo’s visit to NK. There was probably a Chinese delegation there as well. Anyone that thinks China could be left out of these negotiations is naive or uninformed.