I have had this happen to me before. The worms are too hot and the are trying to leave. Just prop the lid up a few inches to allow gas and heat to leave. My bed is in an old 15' freezer and I have it under a shed and some shade. I have had red wigglers for years with no problems after I propped the lid up. They will not try to escape once the bedding cools down. I feed mine vegetable matter from the kitchen. They LOVE cantalope and watermelon....high sugar content. During the Oklahoma winters I add a light bulb to keep them warm. Coldest part of winter I use a 60 watt bulb and near spring I switch to a 25 watt. The lid is still propped up all year. You will get a large population of soldier wasp larvae eating your food but the bluegill will eat these too. Watch out for fiddleback spiders!!!!!!! They like warm dark environments. I have some trophies!!!

Your worms should go right back into their bedding if you let the bedding cool with the lid propped up. Good luck