And even if the cooperation doesn't last, it's an opportunity for the open source developers to work with the product engineers and get direct information from them right now. There's nothing as valuable as talking to the guy that actually designed the thing, or the guy who can make changes to the product code.
Even if that relationship doesn't hold long term, the information gathered in the short term will be useful.
If I were part of this project this is what I'd be going for. Push the company to give you direct contact with the relevant engineers, right now while the negative public opinion is fresh and they're most willing to make concessions, and then get as much out of that contact as you can. Take them at their word, make them actually back it up, take advantage of the offer to cooperate. Sort the rest of it out later.