In one of my attempts, I also experienced a fight where I won but I had my party wiped seconds later, since the game went back to real time and every companion had the SPLENDID idea to improvise a cheerful stroll in a pool of lava in an attempt to RUSH toward the character I had selected in the moment the boss died. I had to reload once again and remember to UNCHAIN the goddamn entire party as soon as the fight started, so "Thanks again, toilet chain" I guess?
Ouch. That is terrible design. So players no basically have to either just unchain every battle, or 'predict' when they'll need to, to save their party.
There should at least be a delay system where they stay put until you click away. Though even that doesn't solve the issue, but makes combat end auto deaths at least not a thing.