Congratulations on scoring an Ebony Fire!
This is one nice thing about the Black Diamond people: they are getting these crepe myrtles out to garden centers and that's a good thing.
We have one entry for this plant:
Crepe Myrtle (Lagerstroemia 'Ebony Fire')
Notice the "Crimson Red" name is given under the "Also sold as" field.
I would absolutely split that plant into two. That's 2 plants for the price of one.