You still can't rule out a smaller band of Maquis emerging even if the majority decided to leave and start over. Number of deaths may have been lower but if people felt that strongly it's unlikely 100% would have gone. It would just run the risk of fracturing the DMZ colonists a bit differently.
The second option doesn't rule out secondary issues like a Federation starship and a Cardassian ship skirmishing by accident in the zone itself.
Your plans may have fewer deaths, but you cannot assure precisely none.
'If the Apocalypse starts, beep me!' - Buffy Summers
'The sky's the limit.....' Jean-Luc Picard, 'All Good Things'
courtesy of Saquist