The SEO tool uses red and green colors to validate or not the connection between the pages, which do not differentiate the color blind. You should add a check, or something else, that identifies if the connection is good or not, that does not depend on colors
We have a similar problem but even worse. Not color blindness but the need for high contrast. We use Chrome with extention high contrast and this ist not working propperly. When page is changed, standard schema is loaded. When you refresh the side, high contrast is displayed. Not very usefull for the handicaped…