You got stuck with something pretty annoying, but you have more options than it looks like. The main thing is don't wait for the resale platform to do something on its own - those websites often just put the problem between seller and buyer and wash their hands of it, so you're gonna have to push.
First, gather everything: photos of the fake tickets, screenshots of the original listing, your purchase confirmation email, and if possible, the message or email where the venue told you they were fake. Then open a formal complaint on the platform itself (not just a private message to the seller). If you paid with a card, call your bank too and report that you received a fraudulent product - depending on your card and how much time has passed, sometimes they can reverse the transaction or start an investigation. With a bank transfer it's trickier, but it's still worth trying at the bank.
About reporting it: the National Police has a specific division for online fraud, and a lot of provinces now accept reports online. The reseller is probably committing fraud, especially if they knew what they were doing. You don't need a lawyer to file the initial report. Meanwhile, keep your tone firm but not threatening on the platform - document every step, every message - because if it ends up in court, that record protects you. Some resellers are people who didn't even know they were selling fakes, but others are straight-up scammers, so be ready for them not to cooperate much.