I would also suggest posting to Reddit's https://www.reddit.com/r/Astronomy/ where these types of questions aren't uncommon.
CZ-5B re-entered over the Indian Ocean about 8 hours ago (10:45am MDT). [https://www.cbsnews.com/news/chinese-booster-rocket-debris-c...]
Five days earlier a 10-foot piece of space debris crashed in Australia - the largest one since SkyLab.
https://www.newsweek.com/huge-piece-space-rocket-falls-sky-l...
It's probably unrelated -- but there's the possibility that an even larger object had split into two chunks, with one hitting Australia and the other taking an additional five days before its orbit decayed.