Not how that works. It would be 4672 * 2.08 = 9718, NOT 4672 * 1.78 * 1.3
So like you said, guy isn't wearing armor, with 0 expertise, while you have wz expertise buff AND something like inspiration just to break 10k. So it is either a setup or a glitch.
Ok thanks for the clarification on that, but yeah still rather improbable..