A hole in my pseudobulb and a mold on my leaf- oncidium twinkle

[WhiteRabbit]

I too only see one (the last) photo ...

Hole in the pbulb could be from some critter, if it doesn't worsen, it's probably not going to be a problem - you can use some cinnamon or hydrogen peroxide in the wound to help prevent rot.

I have never gotten mold on living foliage ...(I believe it feeds on dead tissue ?) when water has become trapped in new growth during cool temps, the inner foliage browns or blackens, and dies. Make sure the "mold" isn't actually mealy bugs - or silk from mealy bugs, caterpillars, spiders ...