I'm so sorry

She has let you know that it has not been a priority for her to never leave the kids with the 16 year old. Off the cuff, she thinks she is always watching them, but didn't worry or intervene when 16yo takes child out of sight to visit the puppy, and you know she wasn't there for the incident with your child.
I see you've read Protecting the Gift...she's given you all the info you need to not believe the blanket statement about the kids never being alone with the 16yo.
She's told you, not in so many words, how it is. She may even believe she doesn't let them out of her sight, but she does do it. And she's taught them how to cover tracks if they are ever accused by daycare kids (I'm not saying she knew one thing about what happened, just that she's had the conversation with her kids that they may be accused. A 16yo predator would very easily be able to do what he did in a way that he could get away with it.
"Mom warned me about people like you. But I'm never, EVER alone with the kids so he must have misunderstood something."
The DCP considering a cya lifestyle for her own children, and "mostly" watching that they aren't alone with the kids, would be fine be except that the boy is dangerous and her first response is to wonder if your child misunderstood.
You know your son. You know your gut. You know that this very sweet lady who is a great dcp, is making light of this and sweeping it under the rug.
"When people tell you who they are, believe them."
(I don't know if this post helps, just thought an outside perspective from another deBecker fan might help)
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