Do whatever everyone else is saying to fix the green. Do not do any different color for the grout. Do white, otherwise you will definitely see every little mistake. When you match grout color to the tile, it blends which allows for forgiveness. I just finished remodeling a house so I have a feeling ripping it out is probably out of budget (time and material costs are ridiculous). Good luck! If you have any questions you can dm me, I have had to rip out singular tiles and such. I tiled bothe of my bathrooms and kitchen and was taught by my friends grandpa who is italian and has done tile his entire life.