Sounds like a respiratory infection. Bubbly eye can be caused by an infection, having the same problem right now. Pretty much the tear duct in the eye gets swollen but I also heard it can be caused by respiratory infection and when you say they have runny noses and have been sneezing it sounds like that

. If you think it might just be a swollen tear duct I am washing my ducks bubbly eye with saline solution and then adding watered down golden seed oil extract into his eye (only one drop of the watered down solution). I’m not sure about a solution for a respiratory infection but I do know that baytril can help with respiratory infection but might want to ask around more! Hope your ducks get better soon