[relaunched]

It's been very open to this ending badly, the more you wish to pursue it. However, if you truly feel like you can reach an optimal outcome, you'll go for it anyway.

Know what you want. Do you want to get paid? Do you want to run it? Do you want to participate in the upside? It's only when you know what you want, can you determine if the deal is fair.

Before opening up the kimono, if you are interested in protecting yourself, you should try to get an NDA in place. It probably won't work, but it's worth a shot. It's also very likely this entire process will sour them on you and you on them. Best of luck!