Can you direct me to any sort of source on that? I did a brief search, and I see some information about toxins found in tomato plants in general, (mostly stems, leaves, and green/unripe tomatoes), but nothing that specifically discusses a higher concentration in the “belly button” (I assume you mean the core/where the stem connects?) vs. the rest of the fruit.

On cherry tomatoes they’re so tiny it doesn’t really matter. You can even eat the stems in larger tomatoes once in a while (though it tastes bad), the amount of solanine left is miniscule. On ripe tomatoes that is.

You now have me wondering if the killer tomatoes in Attack of the Killer Tomatoes are venomous.

They’re not. Trust me, my niece ate almost nothing except grape/cherry tomatoes for the first 4 years of her life, she’d never have made it. I’ve personally eaten whole cherry tomatoes more days than I haven’t in the last month and I feel great.