Help with Lemförde hybrid and other Angraecoids

[Jenn4a]

Okay, I figured I should ask before it's too late..
What should I do with my Angraecum equitans? The 3rd leaf from the top has fallen off. I'm worried because it's not an old leaf.

I've been watching the leaf axils, and there's a couple that turned yellow, to orange, and then finally reddish brown. I sprayed peroxide on the suspicious areas last night, and then put two drops of dragon's blood on the orange areas. (I spread it around to make a thin layer.)
I just looked, and I saw that the leaf was missing, and the parts still attached to the base are orange and red. Hopefully this isn't the dreaded stem rot? The leaf is still green except where it detached.

I have both Bonide Copper spray, and CuSO4... I have generic Cleary's too. I'm not sure if Angraecoids are sensitive to certain chemicals.