He died in 2020 due to natural causes (he was 92, COVID wasn't the cause of his death). In Ben Hur he was Jesus; we never saw his face because of a British law that forbade the showing of Christ's face in a theatrical production/movie. So basically, if MGM wanted to make money in the UK showing Ben Hur, they couldn't show Jesus' face in the movie. From what I've read, I believe that only one wardrobe continuity photo of Heater facing the camera is known to exist. That is probably due to the fact that in the film he was photographed at virtually every angle except face-forward. So the continuity photos probably concentrated on making sure he looked consistent from whatever angle he was being filmed for that scene.
https://www.sfcv.org/music-news/fare...ectacular-life
https://www.hollywoodreporter.com/ne...was-92-1297404