The triggers for obj_unify_culture are busted in CI. According to the 1.30 patch notes, Paradox fixed the vanilla objective and it now uses a different trigger, "has_unified_culture_group", which as far as I can tell just checks that a tag owns all provinces of its culture group. I tested the new objective triggers in my fork, and it works like a charm.
The triggers for obj_unify_culture are busted in CI. According to the 1.30 patch notes, Paradox fixed the vanilla objective and it now uses a different trigger, "has_unified_culture_group", which as far as I can tell just checks that a tag owns all provinces of its culture group. I tested the new objective triggers in my fork, and it works like a charm.