The show has shown us all manner of fates. Is there ever a mention of this group of Lannister soldiers outside of Arya's only interaction?
They, or Ed, appear to have survived the peacekeeping at the Twins but Ed apparently got his face melted when Dany attacked the Lannister train.
Craya: That boy Eddie.
Dirah: The ginger?
Craya: That's him. Came back with his face burnt right off. He's got no eyelids now.
Dirah: How does he sleep with no eyelids?
Game of Thrones, Season 8 Episode 1, “Winterfell”
As there was a slaughter there I’d imagine they all either died or were injured like Ed. Of course if they did manage to survive, like Ed, they were presumably back in King's Landing when Dany attacked it. As Lannister soldiers were slaughtered even if they surrendered it's 99% likely they are dead.