Instead of learning more about the dangerous situation, why yes... let's all just hide and not tell anybody. Not even our generous hosts, friends and allies. AAAAA SOMEBODY BONK THEM ALL
Isaac better not die in this duel. Havel lost some of my respect for bowing to his family's treachery. Could he not, you know just take Marie and guard her? But yeah, he too had his mind poisoned about the "impending doom" of Arcadia.
This makes Kazura look like a moron for blindly trusting Alondo, yes? Now if only somebody, whether Valetta, Zirconia, Havel or Marie said anything about his two-faced character... but apparently proper communication is nonexistent in this story, nobody is capable of saying anything meaningful until the last moment.
Now that the treachery has come to light there's no going back to twiddling thumbs with an oblivious smile. War will probably soon follow since IIRC the Lewsons are intending to time their betrayal close to Valvert's invasion.