Is it permissible to build a sponsorship platform that allows betting sites as an "opt-in" choice for users?

**I am currently planning to launch a digital platform that connects sponsorship seekers (e.g., athletes, sports teams, influencers, social or educational events) with potential sponsors (brands). I want to ensure that my business model and income are 100% Halal according to Islamic Sharia.** In the sports industry, betting and gambling companies are major sponsors. I am considering a system with the following logic: By default, the platform will only show Halal/Ethical brands. However, I am thinking of adding a feature where a user (seeker) can manually "opt-in" or check a box to receive sponsorship offers from betting or gambling companies. If the user chooses to opt-in, the platform will facilitate the connection and I might earn a service fee or commission from that transaction. My specific concerns are: 1. As the developer and owner of the platform, would I be sinful for providing the infrastructure and "option" for Haram activities, even if the choice is made by the user? 2. Would the commission or service fee earned from a betting site sponsorship be considered Haram, even if the user explicitly requested to see those sponsors? 3. To discourage betting sites, if I include a clause in my Terms of Service (ToS) that any betting site registering under a false category will have its payment forfeited, can I keep that money as a penalty, or must it be donated to charity? I want to build a sustainable business but do not want to compromise on Sharia principles. What is the scholarly view on this "opt-in" model for prohibited industries?