The only real alternatives to trying at slow times of day are creating their characters elsewhere and then doing a paid transfer to Mateus, or else choosing a less crowded server for all of you to gather on. In the later case, you'd need to decide whether to transfer your own current main character there or to start a new alt. (If your friends are new and still at the game's starting point, a fresh alt who could be going through the early game with them might not be a bad idea anyway.)