No, he warned him about staying there because he'd be alone. When he said that Morgan couldn't expect others like him to appear, that was sarcasm, meaning that Morgan was pretty dangerous anyways, and that the cabin was fairly remote.
The dialogue--
You can stay here. You have enough food, power, security. For the rest of your life, you could stay here.
But you shouldn't stay here. Can't expect such a splendid guest as yourself to show up
Was a bit of sarcasm, but I do think he was also offering a sideline compliment about the real Morgan he uncovered (considering Eastman's background), as he believed that insane man was not Morgan's true self, and that real Morgan might end up encountering dangerous people.
Again, I say there's no longer any isolated places from wandering strangers. Randall's gang found the town near the Greene farm, Joe's gang knew no borders, the mutilated bodies discovered by the Governor 2.0 group were located in the middle of the woods, but again, someone found and killed them. Even Rick's rescue party stumbled across that isolated, crazy man (who was killed by Michonne).
No one is truly isolated in that world.