I am sorry for this delayed reply to your gardening question. We are transitioning to a new Q&A system and your question was unfortunately lost in the transition. I have discovered it now and hope this reply is not too late to be of help.
Very strange situation with the camellias. If the soil stays too soggy wet that can harm plants but not so fast. I suspect something may have been put on the bushes or in the soil, such as a weed killer applied to the turf or some chemical to the surface and then watered in.
If whatever caused this is not deadly to the plant it should put out new foliage in a few week. All I can suggest that is in your control at this time is to dig down a few inches around the roots and feel the soil to see if it is too soggy wet. If so don't water any more until it is slightly dry (hardly moist) to the touch.
Thanks for the question. Please stop in again soon!
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