From my personal experience, I don't trust any fake book, even the so-called "legal" ones. They are full of mistakes. Before learning a tune, I always check the original or the most popular recording for chord accuracy.
The same thing applies with iRealPro charts. For jazz tunes, it can be tricky, because there are so many versions of the same tune and often with different reharmonization (and lots of freedom of interpreting chord changes). Most of the time, I would go with the original recording or most popular version. For any other versions, I usually specify the recording artist in the song title. It's also not a good idea to post a chart in the forum by simply copying it from a fake book without verifying the chord changes.