No clue what these are

[Maritimer]

So it doesnt move ever. Its been in the spot for two weeks now and it doesnt look flexible. I was surprised when all of a sudden it formed little balls on the tips and then released them slowly because there had been no change this whole time

With this info, some sort of sponge does seem most likely. There are some that I've had in my system that seem to be mostly a web of interconnected tubelike structures, with no "sponge" in between them - perhaps it's something of that ilk, dwelling inside your rock, with just these few bits visible.

~Bruce