Eliza Jones was a fan of Charles Abbott's horror books. He kidnapped her younger brother Sammy to use as inspiration for his Fearsome Frights series of books.
She met the Twelfth Doctor at the 2016UK Book Festival, where she scolded him for writing in a copy of 1001 Facts about the Universe. She told him about her missing brother. He took her to Antagonista, where they saved Sammy and trapped Abbott in the writer's block. (COMIC: Shock Horror)
If a medium is not mentioned, then this incarnation did not have companions who were original to that medium; it does not mean that this Doctor failed to appear in that medium.
