I mean they did decide in Unkillables to stay behind instead of getting to the arks, after talking it out with Gordon they decided that at the time only the three of them wouldn’t be able to get all the orphans, I believe near 50, there safely and stayed to defend them as the arks left. So they can’t be to upset about it.
Also fun thought, what would you name the magic/kryptonite sword? Like I feel a sword like this would have an awesome nickname, it might sound dumb but I’d suggest “Raoslayer” or “Excali-Kr”(the scientific symbol for kryptonite).