sounds to me like you're needing to compost rather than depend on worms - your 2 lbs of worms will eat about 1 lb a day, which means w/ 2000lbs you actually have more like a 5½ year supply! be a long time to "done" :)

setting the bag on the ground instead of hanging it will make emptying easier - mix generous amounts of carbonaceous material, like the paper, also leaves and sawdust, and add a bit of soil or older composted material [or worm castings] to get the necessary microbial life in your isolated, closed system, and stir it up regularly - the worms will eventually thrive and multiply, but it'll take weeks, if not months, for the composting to reduce the volume

w/ primarily grass, which is very high N and very low C, you're creating anaerobic conditions very quickly, generating that heat in the top bit, which won't last long even tho the bags are porous - won't be too attractive for the worms to move up, but more a mass of wet, compacted slime

Bill

You've just saved yourself big bucks - you've reinvented The Swag!

http://www.workingworms.com/swag.html