Is this fusarium on my oncidium? Or?

[meliana]

One of my NOID oncidiums-- when I bought it, it looked like mechanical damage, but it's spread quite a bit and the purple makes me worried. Right now it's confined to one of three bulbs and the rest of the plant is doing well, good roots, just finished flowering and sending out a new growth right on schedule.

From the same nursery, a phal that I bought has a sickly yellow-grey caste to it and the leaves are just starting to show signs of wrinkling. The rest of my phals are rather dark in color as my lighting situation is not optimum, so there's definitely something going on...