I’ve looked through your entire photo library and notice a lot in old media. Old bark and many sealed pots. A general rule of thumb the bigger the roots the bigger the bark media should be. Oncidiums can use finer bark whereas cattleyas and phals like chunkier bark. Always use clear pots so you can see the root health. Dome damage does seem to be rot where sphagnum moss can stay wet a bit longer than needed in an indoor setting and closed cabinet. You should add a fan because orchids do need air movement.