I am not sure exactly what’s going on but it may not have anything to do with Eve, given the text of the error.
These days, SSL encryption on the web is basically standard. Everyone is doing it, pretty much. In order to use SSL encryption, the server and the client (the client being you) use a private and public key from what is called a certificate. The client gets the public key, and the server uses the private key, which it keeps private. To ensure a certificate is authentic, it is signed by a “Certificate Authority”.
The certificate authority can be anyone and the certificate will still work, technically, but browsers have a list of certificate authorities that they trust to avoid anyone pulling shenanigans by trying to pretend to be a domain’s legitimate content when they’re not. Those on this list may sign their own certificates, or a certificate for anyone else, and the browser will accept it. The error you’re getting indicates you’re receiving a certificate that was not signed by any recognized authority. The launcher, being basically some kind of embedded web browser to the best of my knowledge, could also trigger this message.
I think it is most probable that whatever browser the launcher is using has an outdated list of certificate authorities, or is otherwise not able to get that list from wherever it sources it. The alternative is that someone is spoofing the domain name for Eve and redirecting your connections to illegitimate servers that you shouldn’t be connecting to anyway, hence the warning.
I know this does little to nothing to solve the problem, but it is my sincere hope that by having a better understanding of what the problem is you might have better luck finding a permanent solution.