If they were shocked then it would no longer be Gregor's responsibility and he could rest. If, however, they took everything calmly he would still have no reason to be upset, and if he hurried he really could be at the station for eight o'clock.
Si se asustaban, Gregorio no tendría ya responsabilidad alguna y podría estar tranquilo, pero si lo aceptaban todo con tranquilidad entonces tampoco tenía motivo para excitarse y, de hecho, podría, si se daba prisa, estar a las ocho en la estación.