Lazy writing is lazy.
Dale seriously suspects Shane left Otis to die after he pointed a gun at Rick. I don't buy it. There's never really beena point before where Dale thought Shane might seriously screw them over, or leave them for dead. Unless I skipped that part somewhere. This is shit. I understand thinking he's shady, but outright lying about Otis? Fuck this. There's no way Dale's behaviour makes sense.
Dale's behaviour makes a lot of sense. He watched Shane aim his gun at Rick for a good minute. That's enough for him to suspect him.The guys also been pushing them to give up on the kid all along, something he doesn't approve of at all.
Then he sees Andrea return with him, and she has sex hair and acting all weird.
The man is jealous, upset, and that means all of his suspicions come to the forefront, what he really believes is overidden by his feelings and he acts out because of them.
Don't buy. It's so forced. Writer's hand is visible, show
Not really.