The final killcam in WW2 displays the "best play of the match", instead of the last kill. So, if someone had some crazy killfeed, that will most likely be the final killcam. It basically shows the highlight of that match.
As for "how" the best play is determined, I think it picks the highest accumulation of points at any given time as a result of kills gained. You know, the yellow-points-sum at the right-bottom of the screen that goes up after each kill in succession.
"This is awarded to the player who, regardless of the winning faction,
exhibits the top performance in the match. Factors for a player's
consideration for the Bronze Star include score-driven events like
kills, objectives, and Division skill use." - co-founder Michael
So kills in succession (like getting a quad feed) could very well be considered to be a Bronze Star. Or like maybe having multiple "Avenger" kills or something like that. So from what I understand of "score-driven events" it does look at the accumulated score of an instance (so for example, if you had 3 kills in a row, you would have +300 as your accumulated score (in TDM, for example), and if there was no higher accumulated score in that match than yours, then you would be rewarded with the Bronze Star).