Cool dream! I have definitely awarded the RC FL and Window badges. Magic would be anything magical that isn't covered by another badge, I purposely left the Magic badge vague to encourage dreamers to try something different. I would say that the sonic-kinesis qualifies, but you might not if you were arguing in the dream that it was scientific. So I will let it be your call. Did you use magic?
And congrats! 
Thanks!
The sonic kinesis effect itself wasn't magic. The physical laws of the dream world did that. There was some magic involved in the initial blowing of the chalk, to make the blast more forceful. There was magic in place to protect my hearing from the loud sound, in case it became too much. There was also magic in the second blowing of the chalk that turned into an a coherent whistle at a specific frequency, though I'm not sure if maintaining it took magic. Feeling the chalk to help zero in on the frequency, based on its response, was probably magical too.
None of them are tremendously flashy. The most overt one was blowing on the chalk the first time. Oh, I just remembered. I also used a bit of magic to cut through the wall of the house with my two fingers.
So if you think any of those are good enough to qualify for it, then I did use magic. The sonic kinesis effect did not feel like magic though, so I wouldn't count it.