This is an earnest question, not a blind "I don't care". I think this is interesting, and I can see some amount of merit in these claims, but at the end of the day it doesn't feel like it matters to me which one it was. It seems like the only change would be "China gets more bad PR" and maybe American racists use this as an excuse to be more racist.
If China knows and is hiding it, I'm still not clear what that changes. They'll still know to improve their safety practices