@Yftg8
I actually think that it was a huge mistake to have apologized and to have said you're happy to stay put.
The change was made to accommodate your disability.
The decision was not made by you.
Now, by saying you'll be 'fine' staying put, you are, in effect, saying to your colleagues ''I never needed the change to help me cope with my disability''.
So now, your employer will be unlikely to be as helpful/proactive again in the future. This may impact you if your condition worsens or if your work performance is impacted negatively.
Your colleagues think that you tried to 'pull a fast one' and were only stopped from 'getting away with it' because someone went to HR to complain.
And your 'colleague' is still refusing your apology and refusing to speak to you !
Please speak to HR personally and privately, and tell them about your anxiety and explain it was the behaviour of this 'colleague' that was the reason you said you'd be happy to stay seated where you are, as you were very anxious to 'not upset' anyone. (You can't win back the 'favour' of this colleague, because that was never going to happen anyway ! If they were a normal, average person they would have asked you about the move in a normal fashion, not 'sent you to Coventry' and run to HR with a 'complaint' ffs )