Given this detection method works so well in the use case of feeding reviewing LLMs instructions, it should also work for the original submitted paper itself, as long as it was passed along with its watermark intact. Even those just using LLMs to summarise could easily be affected if LLMs were instructed to generate very positive summaries.
So the 2% cheaters on policy A, AND 100% of policy B reviewers could fall for this and be subtly guided by the LLMs overly-positive summaries or even complete very positive reviews (based on hidden instructions).
That this sort of adversarial attack works is really quite troubling for those using LLMs to help them understand texts, because it would work even if asked to summarise something.