a small chance not a big one. most of the times abusers don't spend any money for their abuse and even if they do, the paid VPNs have better IP addresses and lots of them so the chances of finding an IP address that was abused and still has its evil points (hasn't gone back down yet) is very small.
but you usually want to buy VPN for other purposes to increase your privacy and also use it to sign up here.
To be fair, VPNs can't offer the same level of assurance as compared to Tor. You just cannot verify if a VPN provider is indeed not storing logs. Even if you were to purchase a VPN, you might as well just pay the evil fees which is way cheaper than using a VPN to create an account.
It's quite inevitable that Tor IPs will have high evil score. Without that, the forum would be over-whelmed with spam and it'll be hard to filter and read. It's a decent trade-off for a better forum but there might still be better ways to do this.