Here is the translation of the text you provided:

"And behold, the language of the author is: 'It is a mitzvah to hurry and eat for the sake of the babies so they will not fall asleep.' And he explains in Mishnah Berurah (paragraph 63): 'He wanted to say, to hurry to make the order so that the babies will not fall asleep when they know that there will not be a long delay until eating, and therefore they will ask what has changed, and you will answer them, and fulfill what is written, 'And you shall tell your child on that day.' And he clarified in Sha'ar HaTziyon (paragraph 62): 'The source of this law is from the Baraita of snatching the matzah for the babies, and as Rashi explains on the phrase 'we rush to eat.' And the intention is, as we wrote, that it is impossible to say that the intention is to shorten the Haggadah, for eating is the main thing.'

And further on he raises another point: 'And it is also possible to say that the intention of the author is that it is fitting to hurry and reach the part of the matzah, so that the babies will ask why we eat matzah and when they are reclining specifically, and why we eat maror, and the matter of dipping in charoset. And even though in the order of the Haggadah they established 'What has changed?' at the beginning of the Haggadah, there is nothing wrong with that, for the main question and wonder of the child is at the moment he sees the action with his own eyes, and needs contemplation.'

The explanation of the words of the Chafetz Chaim, who is unsure if the main fulfillment of the mitzvah of telling the story to your child is done through reciting the Haggadah, or perhaps it is at the time of eating the matzah and maror, which arouse the wonder of the child until he asks. In any case, it seems that the recounting of the Exodus story calmly and at length comes after eating.

Indeed, according to the Rambam (Chapter 7 of the Laws of Chametz and Matzah, Halacha 3), who explains that 'snatching the matzah' means they snatch it from each other to cause wonder in the children so they see and ask, and similarly according to other early commentators, who lift the plate to cause wonder in the children, or snatch food from them so they do not fall asleep from eating too much, we do not find the need to hurry in telling the Haggadah before eating. Therefore, according to their opinion, it is appropriate to say the Haggadah calmly, without rushing."