Lily makes for a perfect sac character since her autoheal clears debuffs as they get applied, and once she dies after 50% there aren't any further debuffs, anyway.
Definitely some decent luck hitting delays off Quatre 1 at points, but his 4 was also left unused and that could have been opened in case of emergency (or for ~12m damage).
The tightest point was just barely hitting into 10% and then eating an ougi. Were it the other way around and 10% happened with three stacks, that could have been a real problem with several turns left on Maria 3's cooldown and no blue pots.
In retrospect, I had expected that Maria would be needed because it'd be impossible to avoid taking a Conjunction at some point, and Societte's healing would be too slow to recover from that, but I think that with an extra delay, it'd have been possible to make it through the entire OD period from ~40%-25% without taking an ougi, at which point Socie would definitely have been better since getting into red health only happened twice, anyway.
no ship/reactor buff, Quatre 120