Same thing happened to me. Not sure if it is all the balcony rails or just some, but I walked right through it and fell to my death.

This happened to me when I was knocked unconscious. When my friend brought me back I saw grey. I lived with that character for over 10 hours of gameplay afterwards always making sure my food and water were full. I never recovered the ability to see colour.

Same thing happened to me. I assumed maybe it was pain related. I consumed over 50% of painkiller pills and it did not fix the issue.