Ok, I finally received an email back. This is it:
"Hi, my sims archives do not contain trojans, as well as my PC. I don't know who create viruses and what are the ways to find their invasion of the computers, but my sims here certainly not to blame, as I check out, and even scanned the program Eset Nod32."
~ I don't know much about viruses or trojans but that site was the only one I had downloaded from that day - I've checked my pc history to make sure - so, he can claim whatever he wants. There is next to no chance the trojan came from somewhere else.