Answer: Unfortunately based on your description I am not certain whether it is still dead or alive. If it were lack of water I think you would have seen a more gradual decline beginning at the tips and working through the plant. Cold damage can cause wilting and discoloration, and there are some fairly common rhododendron diseases that can cause this plant to wilt and discolor very suddenly and quickly. I would suggest you consult with your local county extension to try to obtain a specific diagnosis and based on knowing that, determine how to proceed. If it is something that can be controlled chemically, they will have the most up to date recommendations on what to use and how/when to apply it. I'm sorry you are having trouble with your rhododendron.
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