Author's Note: For those who already read Watership Down Miniseries Remake: Necklace of El-Ahrairah and seen the actual miniseries, I wanted to answer the question to The Sapphire One. Why I spared Holly? When I first saw the miniseries on Netflix, most specifically The Raid episode, I fall in interest of Captain Holly, as his role was shown more, unlike the movie and the TV Series. Especially to my surprise since I knew in the book and supposingly in the movie that Hyzenthlay becomes Hazel's mate, I liked the idea in the miniseries that the two become mates. However in the final episode their romance was short lived, as Captain Holly saved Hyzenthlay's life (since she saved his life during his escape with Blackberry and Bluebell) in cost of his own life. At the first time I've watched it two years ago, it was a surprise because I didn't expect he would be killed off. However, after watching repetitively, I started to feel very sadden not only that Holly was killed, but Hyzenthlay was broken due to that her mate was killed, as if I lost someone so dear to me. And that's why I had the main character, Kevin, became close to Captain Holly as a Father and Son relationship.
Finally the second answer to your question The Sapphire One... how close would the main character would be with Captain Holly? Because if they are meant to be close, perhaps you could try something that he would do for someone he is close to, like Hyzenthlay. However, about Orchis... you could perhaps do a trick regarding about the main character being kidnapped and than Holly attempts to rescue Emily.