Here are the first 10 survivors possible to be saved
Case 1
Denyce- During your first run for Zombrex she will be in the pharmacy
head to the Yucatan Casino.
BOSS: Ted: As soon as you enter there will be a cutscene, Kill Ted
Snowflake: The Tiger, will start as a Boss, DO NOT try to kill her. Instead pick up the steaks and when she charges throw them in between u and her. She will eat the steak. Once she reaches full health She will become tame, and will follow you.
Lenny: In the managers office after the Snowflake bout, he will show you how to start the slot machines in Yucatan, then he will follow you.
If your fast you should have just enough time to get the Zombrex back to kayte.
Lashawndra: Just outside of the maintenance room during the first case, she will join you without any issue.
Gordon: In the womens clothing shop near Lashawndra, bring her over and he will join you.
Don't waste time taking them back to the maintenance room, just give Gordon a weapon and move on.
Chad: Outside of the pawnshop where the Ones Man's Trash mission is. He is fighting zombies with a shotgun, clear out the zombies then talk to him.
Doris: Lost, she is in the arena area shooting a zombies you will need Chad with you or she wont join.
Kenneth: Welcome to the family, clear out the zombies then talk to him and Jack they will join.
Jack: Welcome to the family, with Kenneth
Esther: Short Sighted: At this point you should have 6 people with you. Just run up and talk to her, after a few conversations she will join. You will need to carry her.