I've found that partnerships such as you describe work easily if you are actively building a solution to a current pain in their industry. They then are happy to help guide you, in exchange, perhaps, for discounted access when it launches.
If your helpers are not interested in such a deal, you might already be missing product/market fit, as anyone who will be willing to pay for your solution would certainly be willing to talk about it.
If your helpers are not interested in such a deal, you might already be missing product/market fit, as anyone who will be willing to pay for your solution would certainly be willing to talk about it.