From my own little language of code and GitHub, I believe all open source code is free to use by anyone. Isn't that correct?
This isn't true, bustadice doesn't give license to their source code. Without any license it only means the source code is available and usually it's interpreted as all rights reserved. But even with license, usually there are few limitation and obligation. Here's snippet from GitHub documentation,
You're under no obligation to choose a license. However, without a license, the default copyright laws apply, meaning that you retain all rights to your source code and no one may reproduce, distribute, or create derivative works from your work. If you're creating an open source project, we strongly encourage you to include an open source license.
And this is very fair, the only thing is we have not used their source code, that is what I was saying, not one bit of their backend was used. To automate playing on such casinos, you can use a written code such as martingale, which my developer used, this is also found online free to access, and that is what was briefly used, however, we understand they were not okay with it, and changed it immediately.