Soil to DWC is definitely the hardest transplant on the actual plant. I’ve done it before and your plant should be fine, it just needs time to adjust. I’m guessing you had it in a halfway decent potting soil to start so it probably had some beneficial microbes to help it take in nutrients in its early stages, most soils have mycorrhizae to help start the plants. Now that it’s in DWC if your not providing the mycorrhizae the plant needs to adjust to life without it, you need to adjust as well. Your pH needs to be kept in the 5.5-6.5 range so the plant can take what it needs, if your pH goes out of range you don’t have that friendly mycorrhizae to compensate. What you’ve done is equivalent to dropping an American with no knowledge of French language in the middle of the countryside in France where the residents have no knowledge of the English language. Your plant and it’s new DWC environment don’t know how to communicate and work together yet and you just fired your interpreter.