Answer: I think only time will tell whether or not your peony will recover from the soggy soil conditions. Root rot is a possibility; verticillium is a disease that is usually fatal to the plant because it infects the vascular system and water uptake is clogged. Now that you've put it in a better draining place, let's hope it recovers. New green growth is a good sign. There's nothing more you can do than you've already done. Water deeply when the top two inches of soil dries out.
Best wishes with your peony!
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