I love beans, but they do need to be soaked for several hours (or overnight) then cooked for several more hours, depending on the beans, until tender. You can check to see if they are done by taking a large bean out of the liquid with a spoon - blow on it gently and the skin of the bean will curl up when they are done. (at least that is how my grandmother taught me to check them.)
I am not sure about feeding more than a few beans at a time to gliders though.
Check the label for cooking time. They may take longer to really get tender if cooked with out salt or the other ingredients usually called for when making the actual soup.
Check frequently during cooking as you may need to add more water as the beans absorb it.
The only problem I see is you are going to have a LOT of beans cooked with out salt or seasonings. More than the gliders will be able to eat. The cooking time will be the same if you fix the whole package or just a small part of it, just in a smaller pot. If you make the whole package, you might consider making a huge bean salad with the leftovers for your self to season them up a bit.
I grew up eating great northern beans, navy beans, pintos, pink beans (very similar to the red kidney beans) and others for dinner quite often. My mother usually seasoned with a chunk of ham, and plenty of salt and pepper. We always had corn bread when we had beans for dinner.