The red duppatta during the Nikah is also a must do in my family too. Because I had decided I wanted to wear red on the shaadi, I wore pink during my Nikah but had a simple red duppatta with silver bordering during the Nikah. I was only wearing it for just for the Nikah itself and no one really saw me with it except for the few girl cousins with me so my aunt just made a simple dupatta.
The first picture with the kiran is lovely! It will go perfectly with green. I dont think you need to be to to matchy if you won’t be wearing it for the entire night since you’ll be wearing another outfit.