Replacing the Wildhelpers script manually, and changing the code as above, it actually works now... To help debug, here is the output:
(From WildShape): copying druid proficiencies: druid pb: 3
-- stat npc_str_save: 4, npc pb: 0, npc mod 4, druid pb: 0
-- CHANGING -- npc_str_save from 0 to: 4
-- stat npc_athletics: 4, npc pb: 0, npc mod 4, druid pb: 0
-- CHANGING -- npc_athletics from 0 to: 4
-- stat npc_dex_save: 2, npc pb: 0, npc mod 2, druid pb: 0
-- CHANGING -- npc_dex_save from 0 to: 2
-- stat npc_acrobatics: 2, npc pb: 0, npc mod 2, druid pb: 0
-- CHANGING -- npc_acrobatics from 0 to: 2
-- stat npc_sleight_of_hand: 2, npc pb: 0, npc mod 2, druid pb: 0
-- CHANGING -- npc_sleight_of_hand from 0 to: 2
-- stat npc_stealth: 2, npc pb: 0, npc mod 2, druid pb: 0
-- CHANGING -- npc_stealth from 0 to: 2
-- stat npc_con_save: 1, npc pb: 0, npc mod 1, druid pb: 0
-- CHANGING -- npc_con_save from 0 to: 1
-- stat npc_int_save: -5, npc pb: 0, npc mod -5, druid pb: 3
-- CHANGING -- npc_int_save from 0 to: 6
-- stat npc_arcana: -5, npc pb: 0, npc mod -5, druid pb: 3
-- CHANGING -- npc_arcana from 0 to: 6
-- stat npc_history: -5, npc pb: 0, npc mod -5, druid pb: 0
-- CHANGING -- npc_history from 0 to: 3
-- stat npc_investigation: -5, npc pb: 0, npc mod -5, druid pb: 0
-- CHANGING -- npc_investigation from 0 to: 3
-- stat npc_nature: -5, npc pb: 0, npc mod -5, druid pb: 3
-- CHANGING -- npc_nature from 0 to: 6
-- stat npc_religion: -5, npc pb: 0, npc mod -5, druid pb: 3
-- CHANGING -- npc_religion from 0 to: 6
-- stat npc_wis_save: 0, npc pb: 0, npc mod 0, druid pb: 3
-- CHANGING -- npc_wis_save from 0 to: 7
-- stat npc_animal_handling: 0, npc pb: 0, npc mod 0, druid pb: 0
-- CHANGING -- npc_animal_handling from 0 to: 4
-- stat npc_insight: 0, npc pb: 0, npc mod 0, druid pb: 0
-- CHANGING -- npc_insight from 0 to: 4
-- stat npc_medicine: 0, npc pb: 0, npc mod 0, druid pb: 3
-- CHANGING -- npc_medicine from 0 to: 7
-- stat npc_perception: 2, npc pb: 2, npc mod 0, druid pb: 3
-- CHANGING -- npc_perception from 2 to: 7
-- stat npc_survival: 0, npc pb: 0, npc mod 0, druid pb: 3
-- CHANGING -- npc_survival from 0 to: 7
-- stat npc_cha_save: -4, npc pb: 0, npc mod -4, druid pb: 0
-- CHANGING -- npc_cha_save from 0 to: 1
-- stat npc_deception: -4, npc pb: 0, npc mod -4, druid pb: 0
-- CHANGING -- npc_deception from 0 to: 1
-- stat npc_intimidation: -4, npc pb: 0, npc mod -4, druid pb: 0
-- CHANGING -- npc_intimidation from 0 to: 1
-- stat npc_performance: -4, npc pb: 0, npc mod -4, druid pb: 0
-- CHANGING -- npc_performance from 0 to: 1
-- stat npc_persuasion: -4, npc pb: 0, npc mod -4, druid pb: 0
-- CHANGING -- npc_persuasion from 0 to: 1