If you are going to provide this "service" for everyone, you should at least obey the GPL, fork this, and post the source code along with the binaries. You cannot change the code and only provide binaries.
Who's going to stop him? The open source software police? Interpol? The Avengers?
Well, downloading something that is open source without available source code is kinda dangerous always. I don't know this guy so he might be trustful. But there are also guys I think it was some russians, that they edited PBE 1.6 and it was stealing something or changing wallet address after copy paste or something like that. And believe me some of my customers also send ETH to different wallets even in e-mails and orders was my wallet due to that paste trojan or whatever is that.
Without source codes you can mine to OP wallet without knowing it... Not saying it does, but there is most likely something shady without any source codes released.