Score one for Kevin, and it's enough to upset his not-mom and make her a little bit suspicious, though unfortunately at the moment she's suspicious of Kevin because she's asking him what was in that glass. His mom's smart though, even a fake version of his mom, and he thinks she'll realize that a borax allergy wouldn't result in that kind of face melting.

That seems to have satisfied the scenario, and as soon as Kevin is free from the hallucination or whatever it is, he bolts as fast as he can go. He's not waiting around to see what Dick might have in store for him.