As it happens, "They do not have anyone to respect" is an accepted translation. (It should also be accepted with "don't.") There are currently no accepted alternatives that use "someone." Since I'm not a grammarian in either language, I can't give you a solid explanation for why that is. But to me "someone" feels more definitive than "anyone," and that may be a factor. In this sentence, "anyone" and "no one" seem to fit better... but that's just one person's opinion.