I can't use the site on my phone, can barely even read any of the text, so I don't know the text you're quoting.

If you are asking if clouds in such a structure are realistic, I'd expect so: clouds do form naturally in even much smaller spaces, e.g. one of the NASA buildings, I forget if it was the Saturn V or Space Shuttle assembly building or both.

The Vertical Assembly Building was used for both the Apollo Program and the Space Shuttle, though it had much more ‘headroom’ for the latter. From what I’ve read the rumors of clouds forming inside of it are actually a myth, though there are condensation and airflow issues. I don’t have citations handy as it’s been a while (decade) since I’ve read this.