In this universe, Ebenezer Scrooge did indeed exist in 19th-century England, a miser who loathed Christmas and good cheer. The Christmas Ghosts, Past, Present and Future, were looking for him to teach him the lesson he needed to learn when they met a different Scrooge — not-all-that-Christmas-hating Scrooge McDuck — and hit it off with him.
The Ghosts eventually returned to the original Scrooge however, and Past felt wounded when Scrooge, having learned the value of goodness, began to spend all his time with Tiny Tim and other friends and family instead of keeping company to the spirits. This drove the Ghost to cling unhealthily to McDuck, to the point of transforming into a Wendigo, so great was his obsession.
Despite his apparent reality, the Christmas Carol story became well-known in the 2017 Continuum just as it was in the Prime Universe regardless, with Webby Vanderquack later recognizing Ebenezer "Bah, humbug!" when her Scrooge McDuck quoted it in an effort to convince his family that he hated Christmas in 2018.