I saw a playthrough like that, and it stuck with Kenny acting like Lee didn't have his back because he didn't directly do anything to help him in the locker.
If you refuse to act in the Meat Locker back in S1E2, you get some...Mixed results. Essentially, for the remainder of Episode 2, Kenny and L… moreilly act as if you tried to save Larry (Kenny's a dick, Lilly says you're cool, etc.). Once Episode 3 starts up, however, the "Previously on..." shows Lee pulling Carley back to let Kenny do his thing, and from then on it's treated as if you had helped Kenny.
A similar result happens if you refuse to help Shawn even after Kenny grabs Duck. The game figures that, since you didn't help Shawn, you must have helped Duck, and so Kenny never gives you hell for it.
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In Wyatt's story, just stay silent the whole time. Believe me, it's worth it...
I saw a playthrough like that, and it stuck with Kenny acting like Lee didn't have his back because he didn't directly do anything to help him in the locker.