Data separated from Model!

better_model.rb

class OurModel < ActiveRecord::Base

  # ... snip ...
  #
  def generate_csv_template(account_id)
    csv_headers = OurModel.human_attribute_name("csv_template_headers")

    headers = CustomModel.find_all_by_account_id(account_id).map(&:name)

    CSV.generate do |csv|
      csv << [*csv_headers.split(/\s*,\s*/), *headers]
    end
  end
end

en.yml

en:
  activerecord:
    attributes:
      our_model:
        csv_template_headers: first_name,last_name,birth_date,pet_name