I have and make hand dipped candy, enrobed pretzels and yes, potato chips. You can easily burn your fingers in the melted chocolate, which, is hot enough to cook a small cherry tomato!
Well it sure sounds like you used a dip prepared differently from what Google showed. If it could burn you, then yes it would cook the tomato. But I have seen strawberries done that way, and even bananas — and no they don’t look cooked. So dear, you should look for a low temp dip recipe. Maybe the higher temp stuff is for pretzels, etc.
Here’s how you do chocolate covered frozen bananas:
Stick the popsicle stick in the banana when it’s at room temperature. Freeze the banana with the stick in it. Melt the chocolate and swirl the frozen banana in it. If you’re fast enough, you can also dip it in chopped nuts before the chocolate hardens.