The receiver of the last payment in a chain A->B->C->D either reveals the secret or forfeits the payment through a refund clause in the transaction. In the case of payments this works as expected, but in my earlier musings for using such a system for data delivery, it would mean that the B and C nodes, which fairly delivered the message, lose out.
The lightning network system is pretty “concept dense” so I’m going to have to reread a few papers to see if I can better understand it. My instinct tells me there’s still something useful that can be applied to paying mesh nodes to deliver data.
Another consideration is that the physical network of mesh nodes may not be the same as the financial network of payment channels. If every pair of nodes had a payment channel between them, it’s easier, but realistically that won’t be the case.
I’ll try to come back with my thoughts soon, it’s fun to think about this problem.