Wow, that’s incredible! I was afraid I would have to do the same after my skiing accident. Couldn’t imagine myself in your shoes, I remember the feeling when I tried to write even couple words with my left. I immediately dropped it as pointless.
Luckily, my shoulder fracture allowed me to scribble at least a little bit with my right so I could somewhat practice. Then, I was extremely fortunate I could write fairly normally by May.
I would say they refused it because of the short time before exam. Anyway, well done!
With regards to the video, personally, I pretty much did follow the video but not 100%. Generally I think it’s extremely useful because it really shows they candidates need to curb their writing and save time.