A journal's pages are referenced by index, not by ID (see the RemovePage function). ID numbers exist, but they are assigned by the Speech Manager when you click "Gather text".
Since the pages List that stores the JournalPages within a MenuJournal element are public, you could write a custom function that iterates through them, searching for a page with a given ID number
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Since the pages List that stores the JournalPages within a MenuJournal element are public, you could write a custom function that iterates through them, searching for a page with a given ID number