In the case of Refn, like Del Toro, the character's appearance is the only likeness shared with the actual person — both were visually captured, but are voice-acted by different people.
Kojima explained as much on Twitter this week:
I asked my bestie, Nicolas, to be “HEARTMAN” in DS as special guest. We 3D scanned his head, body, and facial expressions to make his 3D model, but his acting and voice are done by a different performer, same as with Guillermo. 👍🌈🦀🐟🐋☔️ pic.twitter.com/wOGt0LfX89
— HIDEO_KOJIMA (@HIDEO_KOJIMA_EN) May 29, 2019