Are they sick or normal??

[Pakmanwong]

Hi everyone! I have recently acquired a few orchids for my collection, and I realized that there are a lot of spots on their leaves and stems.

The first four pictures are on the Dimeranda stenopetala, white to yellow marks on the tip of leaves, groups of black spots on the underside of a few leaves, and black spots on stem. I saw a few ants crawling on it today (I reported it as soon as it arrived, it was potted in sphagnum moss and oasis, I tried my best removing everything and reported it in medium and fine bark chips with charcoal and perlite)

The fifth and sixth pictures are on the den. unicum, there are a few light indents on the leaves making them look wavy, they are not mushy or soft, hope you guys see it and get what I am telling (I am not talking about the white spots from the spray that I used on them and I did not repot it).

The last picture is den. pierardii, the stems have many purplish spots and smooth in texture. I did not repot this plant.

Would everyone please help me identify what they are, good or bad, and how to treat them! Thanks a lot!!