Below are two histograms. The first one shows the win rates of RBs with an ADP in Round 10 or later from 2015-18. The second one is the same thing but for 2019.

The 2019 median was in line with previous years, but there just weren't any high-end (read: league-winning) outcomes.

Chase Edmonds had the highest win rate among late-round RBs last year at 11.2%. Previous yearly leaders:

2015 - Danny Woodhead (17.0%)
2016 - Jordan Howard (14.6%)
2017 - Alvin Kamara (20.8%)
2018 - James Conner (21.8%)

And then Edmonds. At just 11.2%.

Win rate data can be noisy, so I should also note that late-round RB scoring was down 20.0% last year.

TL;DR: It was a really bad year for late-round RBs. They should rebound in 2020.