Both Seth and Kate consistently landed headshots with their weapons, which would kill Strigoi, making them the two most likely survivors of this encounter.
Does Richie die in From Dusk Till Dawn?
As the brothers argue, Seth knocks Richie out, breaking his glasses. Unfortunately, the blood from Richies causes Santanico to go into a frenzy, and she bites him. Its then revealed that he turned into a vampire and confronts Seth. He is then staked by Seth, killing him.
What happened to Kate after From Dusk Till Dawn?
After reuniting with Richie Gecko at the end of Season 2, she was killed by Carlos Madrigal, while trying to save her brother. Kates body was left at the blood well, where she was resurrected by the Santa Sangre and became possessed by Amaru, Queen of Xibalba.