If you read The Writer's Tale, RTD wrote the character of Midshipman Frame in "Voyage of the Damned" for Russell Tovey because he had a crush on him, and also wrote him getting injured to try and give him an excuse to take off as many clothes as possible. At the time I read that, I didn't pay it much heed and wrote it off as a bit of harmless fantasising, but thinking about it now and particularly thinking about it if the sexes were reversed (i.e. it was a male writer writing that about an actress) makes it seem very creepy.
That said, RTD also related a story where he was talking to another member of the crew and they said to him: "You must be the only producer who fantasises about sleeping with half his cast" and RTD replied: "I'm one of the only ones who doesn't actually do it."
I wouldn't be surprised if Moffat had some skeletons either. He said that after his divorce from his first wife he shagged his way around studios like a mechanical digger (his exact words), and he never passed up a chance to get Karen Gillan in something skimpy.
Much as I may dislike his writing, I think Chinballs is the least likely to have done something dodgy. He seems like too much of a wimp and his writing's so sexless I really can't imagine him trying anything on. Then again, there have been some surprise sex pests before, so I wouldn't rule anything out.