I just got back from a conventyion and I wound up forgetting the name of an artist who made one of my commissions. They didn't sign it, so I can't give them the credit they deserve until I find out who drew the piece for me. How should I find this information out?

To give an idea of what the image is, it's a robotic MLP style unicorn with a straight mane and tail manipulating the pieces of a toy robot in her telekinetic aura. On her flank is a pixelated screwdriver. The picture is black and white, done in pencils. The convention was Fur Squared 2020.