there are more possible scenarios

For example:

Someone saw that Wang was sacked. He just spread the rumor that Wang and Bo broken up because Wang rat Bo out.  It was a believable story that completely came out of thin air. I know a lot of people would like to bull-shitting about political stories. Somehow VOA started to spread the news. The domino started.

By the way, (3) is impossible since the last thing Chinese government wants to have is the interference from foreigners to internal affairs. This is the biggest taboo of Chinese culture.