The reality is no one, from the captain on down, will confront the cigar smoker. I have watched every officer walk by as he smokes and I have not seen one person say a word to him. Maybe he's a major share holder.
The smoking rules are quite clear about where you can smoke cigars so this should be a non-issue.
The problem is no one gives a ship! (spelling intentional).
We saw the same indifference on the Silver Spirit the past spring.
This is probably our last Silversea cruise.