At one point, Richard Wheatley forces Elliot Stabler to claim responsibility in ten officer-involved shootings over his career. While some of those can be accounted for during his tenure at SVU and Organized Crime (most notably Jenna Fox), the number doesn't amount to ten. Presumably, some of these shootings likely occurred while Stabler worked for the unnamed task force in Italy from at least 2017 until his return to New York City.
This episode marks the first appearance of Frank Donnelly, whose storyline officially begins in the following episode.