If Frankenstein's dream is defined as the accomplishment of science to do what had not been done before, then one could say that Frankenstein did achieve his dream.  His ability to use science to make a living being is something that represented the culmination point of his efforts, his drive, and his dream.  Certainly, with the creation of the monster, his "hideous progeny," accomplishment was present.  The more interesting implication that results here is that the creation of his dream actually results in being a nightmare, and within it, the development of the theme of the danger of appropriating the world in accordance to one's own subjectivity emerges.