Some things from Law's plan just aren't making sense to me. If he knew someone would come and wasn't sure it was Doflamingo until the phone call (at which case they were already at sea), why did Law say that they must leave in a hurry no matter what? Even if it was Doflamingo, why not wait and kill him when he comes to Punk Hazard? People that may say "Doflamingo could kill them all!".. well then that wouldn't make sense since they're going after an enemy that looks stronger than Dofla since he was scared when he heard Law told him that Kaido would destroy him.
He also said there is something in this island that can help us win or a key (don't remember the proper phrase), is it Ceasar? Or is it Kuzan or something/one else? If it is Kuzan, did Law either get in an alliance with him or simply create a plan in which Doflamingo and Kuzan would meet at that specific time and he would crush Doflamingo? Or does Law need Doflamingo alive so Kaido opens up his forces and sends them after Dofla which will leave him exposed and in that moment the alliance will attack?
His plan is very confusing atm but it's obvious that we don't know enough, I just don't understand why they didn't wait for Doflamingo/or someone else that Law thought would come and kill them. That's less obstacles in the way.