We recommend watering the area as much as possible to reduce the stress on the plants and reduce the action from the Weed n Feed. Cut off any of the wilting/damaged parts of plants to encourage new healthy growth.
Apply 'Yates Dynamic Lifter Liquid Concentrate' as a gentle fertiliser and soil improver. It's certified for use in organic gardens, and contains seaweed, blood&bone and fish meal to help developing new roots and restoring healthy growth. Click here for more info on this product: https://www.yates.com.au/product/garden-fertilisers/certified-organics/yates-dynamic-lifter-liquid
This should be applied weekly until the plants are looking like they are recovering.