Answer: I am so sorry! This sounds like a case of fertilizer burn, yes. Whether or not they will survive depends on how much damage was done to the roots. If you can still see clumps of fertilizer, remove it. You could try watering heavily twice in one day to try to leach the fertilizer deeper into the soil so it is below the roots. (More than that would possibly cause overwatering damage to the roots.) Basically, you will have to wait and see. I would wait a while and see if they releaf. Any twigs or branches that are dead can be removed, but it will take some time to be certain they are truly dead. I hope they are okay!
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