Phandelver module art and rollable tables (minor spoilers)

I recently purchased the Lost Mine of Phandelver module, and am sorting through it prior to play. Everything looks to be in order, except that in the Cragmaw Castle map, the token for Vyerith uses art for a doppleganger (the PCs are supposed to think she's a drow at first).  I was hoping to use the rollable tables feature to create a new token with two faces- the existing doppelganger face and a new face for the drow- but as far as I can tell there's no way to get the doppelganger token image into such a table. In fact, I can't seem to find any way to interact with any of the art assets at all, except to copy and paste tokens between pages, which has me worried about what would happen were I to delete an important token. Am I missing something, or is the module content as locked-down as it appears?

You can open up the Doppelganger character sheet, press edit in the top right, and it will open up another page, where you can save the image of the token presented there. After you make the rollable table tokens, give them the stats, and add them as tokens in the page where your ipped the token image before, that way every doppleganger you create will have the same multi-sided token.