The law is not stupid. Person C is stupid.
Stupidity of not knowing is guilty these days.
You got pulled over for speeding, but you can't say you didn't know the speed limit. Judge can consider the situation, and lower the penalty, but you are still guilty of not knowing.
"Person C unknowingly/unintentionally received stolen fund"
Come on, don't be so naive. In reality and in most of cases, Person C knows where this fund came from which is not so legal source.
You're talking nonsense. Stop with this. The chances of someone sending you 10 BTC by mistake are the same as some thief sending it to you.
As I've already stated Person C did nothing wrong. His wrongdoing will start if he refuses to cooperate.
all of them?
No. Stop replying before reading the thread.