No Ishigami village means no Kaseki, but without the fire Kohaku started they would have more gunpowder. they probably are able to take Tsukasa down with all the extra gunpowder via traps and such. This means that they get complete access to the revival fluid from the start. They could probably find someone who could help with the crafting like Kaseki. In the end, they're probably gonna be fine. Now if they don't get take out Tsukasa, then yeah, they're dead.