No, it was probably a .223 or 5.56x45, the most common chambering for a AR15 clone.
The term AR15 clone is used because it covers the many different manufacturers and models that are made on the basic AR15 type of platform.
It has not been stated where Deishun L. Byrd-McWay was hit. There were likely peripheral hits, as he survived.
I have an AR, and it certainly isn’t a clone.
I have seen 9mm, .22 cal, and even BB firing AR's.
I just watched the video, and, from the muzzle flash, looks like you’re are correct about this guy firing a .223/5.56.