If you read between the lines of The Mummy, you can see what should have been the central story of the Dark Universe’s origins: the origins and purpose of the secret organization Prodigium.
Unfortunately, The Mummy really should have been “Prodigium,” which could have told the story of Dr. Henry Hyde and his own personal fight with evil.
Should Universal want to be serious about involving the audience in its Dark Universe, it’d be wise if the folks in charge set Hyde’s story as the true north to the rest of the series, rather than merely include a Russell Crowe cameo to somehow fold Bride of Frankenstein into the mythos retroactively.
With easter eggs and nods to other films in Universal’s canon littered in the stretch of the film focused on their gothic, yet high tech, hideout, it’s the usual tease-laden sequence that you’d expect from a universe building film.