[Hi Mazzamada,
I will definitely try this out next year, (the hornets are winding down now here in northern Thailand). It makes a lot of sense. We have had no measurable success with poison-&-release this year or last, but we weren't using food attractants in the paste, and poisoned hornets were only living around 15 mins. So your method sounds a much better approach. Your ideas have already been circulated on the Thai bee keepers association group chat, so I would expect several people to be trying this out next year. Looking forward to hearing about the additions to the mix.
This year, we also tried French style museliere (muzzles) that fit over the bee entrance and seem to have had some success with reducing predation by using two vertical screens of single wire, at 3cm and 2cm spacings. The two screens were placed 10cm apart. The idea being that whilst the bees could easily fly through the outer screen, (3cm) and negotiate the second screen (2cm) fairly quickly, the hornets do not like to enter the first chamber, and very rarely enter the inner chamber. This seems to reduce pressure/stress at the hive entrance. As a result we have managed to maintain colony strength through the wet season.
Thanks again to Mazzamada for sharing his information.