It would not be an issue, we just have to get creative. No problem.
How tall is your vaulted ceiling?
Is your shower tiled all the way up the walls and the ceiling of the vaulted section?
Standard and best performance height is 7 to 8 feet high.
Can we install a glass paneled ceiling at the top of the shower height?
When calculating the adjusted cubic feet for your shower we would have to make an adjustment for every foot over 8 feet.
Feel free to read more about Ceiling Heights