Nothing wrong with you having an idea, but in order to create something where quality and security is the main point of attention, you'll need top notch developers and designers.

You can't expect them to offer their services for free while these people are wanted by basically every serious business where they are being paid greatly for their delivered work. Quality and security comes at a price.

You are aware of how many free gambling/casino scripts there are out that you can customize to your needs and liking? You just need to look them through for bad code lines put in there to potentially clean your hot wallets.