Victoria is a narrative stand in for both the Dr and Helsing. (That’s why she has the crossbow in the key art.)
In the queue it explains how she’s devoted her life to tracking and capturing monsters. I think she may even have Van Helsing’s journal which helped her learn weaknesses.
But she’s also restarted her great great grandfather’s research and created her own Monster.
Why did they do all this? Go through so much trouble when they already have preexisting characters and stories? Because Dark Universe is an original land, it’s just inspired by the Classic Monsters. And by bringing the stories into present day, it gives them the excuse to create whatever they want, building upon the lore, without worrying about timelines, plot holes, or logical inconsistencies.