Had to click over and see the worms. What's your method for harvesting the castings?
I wait until the bottom of two bins is almost solid castings and then dump it on a big piece of plastic. The bin in the lower right of the picture above is a bin that is ready to be dumped. See how smooth it is on top? That's from the bin that sat on top of it. As the food disappeared and the worms in the bottom moved to the top box the castings got squished together. Usually there are some shreds of newspaper left in the bottom after I dump it, but they are easily removed and put into the top bin. It takes several months for the bottom to become mostly castings .
Black soldier Fly Larvae (the other cocoons) I have those in my hot compost heap - they are voracious little composters...and don't harm the worms. Happy Composting!