The first question is the problem. If the aliens have an analog rule (“Do they possess our intelligence or greater?”) then it only works if humans and them are roughly the same intelligence.
That definitely could be true. My first reaction here is that it will be dependent on the 2 species. Every sentient species pairing combo would be different because it largely depends on how much the less advanced species is capable of comprehending. That gap between the species along with the absolute intelligence of each of them both matter.
I don’t quite know if I think it only works if there is parity because there has to be some room for agency for the “dumber” species if they are sufficiently ontelligent. It might be such that a species is smart enough or advanced enough to understand the risk they are taking despite not understanding the act itself.
But I’m not sure how set I am in that because I can imagine problems depending on the “advanced” species capability. What if they can inject the right combo of chemicals into your brain to make you love them no matter what they do to you…that could go bad quickly. Certainly that wouldn’t be moral, but there are situations imaginable that are far less extreme then that which would be fine.