Mostly dead roots (Phrag, Oncidium, Cattleya, Laelia, Maxilaria)

[estación seca]

A questionable Den. kingianum in mushy medium going into winter isn't likely to survive. I would unpot it, hose off the old medium, not remove any of the plant that doesn't fall off, repot into very large bark, place into the brightest spot possible for the winter, and water once a month. If it's going to live it will start making new roots and growths when it warms up in Spring.