I come up against this longstanding problem all the time. I’ve started to just assume that whenever a mainstream-ish film has no director credit, it’s because the name contains an apostrophe. Furthermore, you can accidentally REMOVE a director’s name if you update the info for a film that already displays an apostrophied director. Whoops.
Hate this. 
Could you please try again. This bug should be fixed.
Let me know if it’s still not working
It seems to be working again! Hooray, thanks! I just bemoan COUNTLESS forgotten examples I’ve found of this problem that I was unable to correct at the time.
Hrm. I did fix some Marcel L’Herbier films, but I still can’t get this director filled in:
https://beta.icheckmovies.com/movies/1929565-yellow+fever-2012
Roscoe ‘Fatty’ Arbuckle now has about 25 more directing credits on ICM, thanks to me. 
I guess the problem isn’t entirely solved, because here are two recent films with apostrophe directors who won’t import.
https://beta.icheckmovies.com/movies/4145126-root+letter
https://beta.icheckmovies.com/movies/4128373-secrets+of+the+oligarch+wives