Is this a valid and convincing diagnosis and treatment for nasal congestion?

I was talking with an older real estate agent. She said she could not breathe through her left nostril so she went to a specialist (ENT). Ten years ago she was riding her bike and fell off it onto her left temple. His opinion was she shattered some bone on the temple and, over time, the fragments drifted down into the nasal sinuses and they needed to be removed with a 7 day recovery. She termed it a “roto rooter.” Six weeks later her nose continues to run and is slightly clearer. Possibly accurate diagnosis or just allergies?