One could argue, according to Cynefin, that "wicked problems" are where Lean and Agile diverge. When you're operating in a generally-known environment where what's unknown are things like product/market fit or codebase behavior, it makes sense to operate in short iterations or kanbans with rapid customer feedback, while still trying to use Lean to drive efficiencies along the way.
But if you really have no idea what's going on, there's no way to know what is "efficient," and so you have to fall back on more pure Agile, i.e. Cynefin's recommendations for the unordered "chaotic" or "complex" domains: do something small, analyze how that affected your environment, learn from that, and respond/repeat.
But if you really have no idea what's going on, there's no way to know what is "efficient," and so you have to fall back on more pure Agile, i.e. Cynefin's recommendations for the unordered "chaotic" or "complex" domains: do something small, analyze how that affected your environment, learn from that, and respond/repeat.