“I survived the mites only to be professionally misted into a rash.”
This Rojo Congo is most likely showing spray damage rather than a root problem. The browned, bronzed patch on the leaf fits chemical scorch from the neem + alcohol + Castile soap mix, especially since you sprayed all the plants and this leaf was the side furthest from the window, which can dry more slowly and hold residue longer. The fact that the rest of the plant looks healthy and is pushing a new leaf is a good sign. This does not look like a whole-plant collapse.
Stop the leaf burn from spreading
The plant likely does not need a rescue treatment right now. Focus on preventing more spray injury and let the damaged leaf finish its course.
Also possible, but less likely
What would prove it
Watch the new leaf, not the damaged one
If the new growth stays clean and the browned patch does not spread to other leaves, this was almost certainly spray scorch. If fresh spots keep appearing on non-sprayed leaves, then look harder at light, watering, or pests.
Turn this into a recovery case
One photo gives a diagnosis. Tracking proves whether the plant is recovering.
Don’t leave the diagnosis hanging 🌱
Save it now, then use the next photo to confirm if this was the right call.
Create account & save plant 🌱