Ohh man I'm so sorry. I feel for you. That is the EXACT same outcome really that I had when attempting to pair up my rabbitfish and then before that about a year ago I tried to pair up two golden dwarf eels. ALL the advice I was given was essentially "go for it because things will be fine" and in both cases the newcomer to the equation died before I was able to separate them. It's such a hard judgment call because there is ALWAYS hazing at first and in many cases this subsides after a few days and so when you're in that period it's so difficult to gauge whether you should wait out that first week and see how it goes, or whether you really do need to do an intervention for the sake of preventing one from dieing. So I was incredibly annoyed and disappointed at the bad advice I was given at the time.
That said, despite my intuition that I probably will never pull it off, I would LOVE to pair my crosshatch one day .. so I was still hoping to hear that there'd be a happier ending to your story than this.
