In @pdg137’s example here’s some screenshots assuming pdg didn’t realise they could break in and pass.
Black connects
White passes unlike the game
Black passes
I think the unsettled stones, namely G9, F8, F7, G7 and F6 should all be marked alive since they’re not pass alive, otherwise one runs into the problem of trying to distinguish “dead” stones in a territory from actually dead stones which assumes katago played on from the position.
It would mean that the players would have to manually mark F6 as dead, but that’s okay, that’s what you want, the players to agree on which stones are dead and not gain any new info from what katago thinks of the position.
One could argue maybe a beginner thinks G3 might be alive, but it’s likely they would’ve tried to save it before passing. It’s hard to think certain stones would be alive anyway…