I’m having the same issue with my ‘15 Big Horn, 1500, Noticed it the other day at Sonic, front windows won’t go down but back windows will, as far as I know the fuse that controls the windows is a 25A fuse, one of the bigger rectangular fuses (or at least it is on mine, I removed it and back windows wouldn’t go down so I would say that the fuse is good, I read somewhere that if the master switch goes out it can cause the other windows to not go down, however I’m not 100% sure if it’s actually all the windows or just the front windows. New master switch is roughly $30 on Amazon, I plan on looking further into it tomorrow though.