Had a job in the week where there were stains from cool aid (bright red) all over green wool carpets,in just about every room,could not shift them at all,used red rx,no col transfer,tried citrus gell and last resort tried solvex just to see,no joy.
Just went over them a lot with the wand in the end andd faded them slightly,felt so bad that i knocked £20 off !
I did mention prior to cleaning that they may not shift !