Should not need to redownload it, I didn't and see them. The individual battalion scroll are under the warscroll section (with refinement, Order - Seraphon they are on top) Here you can click them and see the mentioned list by Crowsfoot. and decide to unlock only the selected battalion scroll. In section "Books" -> BattleTomes you can buy the whole digital battletome to unlock all the battalion scrolls for that battletome. In section "Battle Packs" you can unlock all the battalion scrolls without buying the digital version of the battletome.