Hyaluron on Coccyx/tailbone?

Hi all, First of all, i am not a native English speaker so i am sorry if i use wrong words.

1,5 years ago i was on a roller-coaster and hit my coccyx/tailbone. (Which is the right word?) I could sit or lay on my back for a few weeks. I was in CT (Computer Tomography) but nothing was found. My doc gave me ibuprofen to release the pain and if there was a inflammation. But again didnt work longterm. I did acupuncture for 15 sessions, visited my orthopedic a few times and also had sessions with an osteopath.

Today I still cannot sit longer than 3 hours on a hard chair, 4 hours on a soft chair. During the whole day. So you can imagine I am in pain nearly every day as I have an office job.

I heard you can do hyaluron of the tailbone. As far as I know it will work like a pillow so the tailbone can heal even when sitting. Does anyone has experience with this or suggestions what else I could do?