> I would simply reply that you cannot share data before publication, but they certainly can see the published data once it is public

We did that. We only didn't respond to the request to meet in person. Sorry if I was unclear.

> I'd be asking for information, too. Not because I want a fight, but because it is simply good practice to understand people's concerns about your product, and have an opportunity to fix the problems.

Good point. Unfortunately, we don't really know _why_ the product doesn't work. We only know that statistically speaking, we have low quality evidence that the impact on tested outcomes is negative. So fixing things won't be easy at all.