I'm going to give you two scenarios and I want you to post how you would feel about Luke in each individual scenario. These scenarios are just hypothetical and not to be taken seriously.
Scenario #1: Luke tries to convince Kenny that they should fall back and live to fight another day. Kenny considers this whining and tells Luke to "take a hike." Left with no other choice and unable to sway stubborn Kenny, Luke withdraws himself from the hostage situation in hopes of preventing any casualties. In episode 3, Luke will track Carver down to his community and formulate a plan to liberate the group. Luke will find the 400 days characters in Carver's camp. He will intentionally get himself caught by Carver so he can persuade the 400 days characters to turn against Carver (just like the cabin group) causing an uprising which is just the distraction that the group needs to set their prison break plan in motion.
Scenario #2: Luke is nagging Kenny that they should escape while they still can. Kenny refusing to leave his group behind, tells Luke to "take a hike." Luke with his keep moving on attitude takes Kenny's advice and runs away. Luke considers the capture of his group as a loss and it's probably best to move on. Luke continues to survive without looking back.
How would your opinion on Luke change between these two absolutely different scenarios.