Hi Don, I did detach one but I haven't seen any sign of a caterpillar emerging to feed yet. I'm reluctant to cut it open if that is what you are suggesting as it is so thin.
Don, Just left the case on the kitchen bench with some Eucalypt leaves nearby. I've found this often induces the caterpillar to emerge. Came back to find the caterpillar partly emerged but quickly retreated. Will continue to check to see if it comes out far enough to get a decent photo. Probably more luck for a good photo during daylight hours. Will keep you posted.
@donhe I've discovered a new technique. Took it out to the deck for good light then as it tried to crawl along a cloth, I held the back of the cone and gently pulled backwards, which pulled the caterpillar mostly out of the cone so was able to get a decent photo.
Super photo. Looking more like Tineidae now perhaps, although that and Psychidae are both in Tineoidea, so some genera in both may look similar. Fingers are crossed.