All perfect praise be to Allah, The Lord of the Worlds. I testify that there is none worthy of worship except Allah, and that Muhammad is His slave and Messenger.
There is no need to panic about this issue. If water pours down on the clothes and drains without having changed due to impurity, then the water is pure, and so are the clothes. The way of pouring the water in washing machines is known, and whether or not you add washing detergents, what is important is that waster is poured over the place of impurity in these clothes are purifies the clothes, if they were impure to start with.
Allah knows best.