Play it off as a joke

This may not be an episode of The Twilight Zone, but you're playing by the same rules. No one believes you, but that doesn't have to be a problem. It means you have more time to figure out what's going on, right? In horror movies, the guy who insists to his friends that the monster's real is the first one who dies. All you have to do is play along, and you should be fine.

You roll your shoulder out from under Sully's hand, and **** out a laugh. "Geeze, you guys are gullible. You seriously thought Pearl changed colors? That's cuh-ray-zee!." You laugh giddily to sell the deception.

"But that's what we were telling you," points out Indigo, looking confused.

Yutong is also lost. "How is that funny?"

Pearl sighs. "It's a 50/50 tossup of whether reason penetrates Chase's skull," she says. "He's hopped up on adrenaline cause of the soda machine. Trust me, you'd rather have a half-assed, lame prank like this than a whipped cream pie in the face."

"Speak for yourself," grouses Jane.

You let out a sigh of relief. Looks like you successfully defused the situation, with your friends none the wiser.

Which means...

Again you peek at the Popple Quench Juicer Max.

You're the only one who knows that the Juicer's soda transformed Pearl. They all still think it's a normal, non-cursed soda machine.

Your friends laugh at one of Sully's jokes. You remain eerily silent.

A once-in-a-lifetime opportunity has fallen into your lap. If you, say, mixed up another drink... no one would be the wiser.

A flash of guilt pangs you at the thought. Are you really going to keep magic a secret from your friends, just for a chance to keep it to yourself?