Walletgenerator.net has had known vulnerabilities since at least 2019: https://medium.com/mycrypto/disclosure-key-generation-vulnerability-found-on-walletgenerator-net-potentially-malicious-3d8936485961

But one other issue is that walletgenerator does not support the creation of Vanity keys...so I'm confused why you even switched to using this software from bitaddress?