The "dog got shot" scene was in the film when it was screened at Cannes because the director surreptitiously put it back in, making a fool out of Ben.
The way I saw the graveside scene, Ben accidently hit Dick Bell with the shovel handle, but he was so frustrated that he didn't catch himself and took the opportunity to let it escalate into a full-out attack. Ben was frustrated because Dick Bell had, at that point, managed to avoid confronting his client about the beard.
During post production the studio doesn't place spies or liaisons in the edit bays to monitor the progress 24 hours a day. So after the studio signed off on what they were shown of the dog licking scene they just assumed that's what was going to ship. After studio heads leave the room, the film is again open to any alteration and any manner of change before being sent off to have prints made. Not unrealistic. Just unlikely as doing so in most cases would be cause for any number of severe consequences.
Plus: The director didn't have to alter the cut after it was approved - he just made two different cuts, showed them one and, when they gave their approval, simply switched them.
- Anwar
--- One man's sockpuppet is another man's freedom fighter.