The more bright stuff you have in your inventory the more likely the worm spawns.
...but how on earth did you get to 30698hp?
Same. I used to have a really funny scene with Pearl, where you could ask her to fuse, but then she told you she was out of your league, and then it killed you as a result of the emotional damage! I ended up removing that because I was going to have her be the quest giver, but I never finished that system (in hindsight Garnet should have been the quest giver, and I really hope the version with that joke got saved on some archive somewhere).