Yes, as everyone who understands evolution is well aware: Observed Instances of Speciation.
You say that "endemic" means "currently unable to survive elsewhere". Presumably this means they could not have come from elsewhere, but in order to say that, you have to ASSUME that the species haven't changed since the last ice age, which is what you are supposed to be showing.
You say that "from scratch" means "from apes", in the case of human evolution. But that gives very little hint of what that might mean in the case of the "endemic" coral, other than "from coral". Yes, I believe that the coral on the island in question DID evolve "from coral". In fact, it's a claim I dare to make. Does that help?
You say that in #127 you are questioning whether coral larvae could have journeyed to Lord Howe Island since the last ice age, and then specify that this be done "from scratch", which you then define as being restricted to the species that "survived the last ice age in Lord Howe". So what you're saying is that the species that survived the last ice age in Lord Howe could not have come to Lord Howe Island since the last ice age. FWIW, I agree.