The last two ones, as of writing this, cannot be read. After 19 entities, bzread returns empty string and feof returns true. Does not happen for the dump before. Does not happen using bzip2 ubuntu package. Does not happen when extracting 1k entities using the ubuntu package, recompressing them, and having PHP go at it. Happens with PHP 5.6, 7.0.0RC6 and 7.0.0-dev.
Wrote a more detailed report, but hit back button, and apparently Phabricator is nice enough to prevent my browser from remembering the text.