> if we don't know if something has qualia (despite externally showing evidence of it), morally you should default to treating it like it does
This would be like treating characters in a book as if they have real feelings just because they have text on the page that suggests they do.
At some level I'd think that "responds to stimuli" is a minimal threshold for qualia. Even the paper the book is printed on responds to being torn (it rips). I don't know of any way to elicit any kind of response from a book character, it's totally static.