Vampire crap brom/orchid paludarium. High humidity.

[harpspiel]

Where is the 90% humidity measurement taken from? Humidity often stratifies from bottom to top of a tank, but if it's 90% throughout with low airflow that's gonna be too humid for many orchids, you'll have your best luck with pleurothallids (which is what you have so far).

By the way, 21-26C is not considered hot, it is comfortably within "intermediate" temperatures for orchids, so if you're searching for species that will be a keyword you'll want to use.