Unfortunately, there is a common mistake. I think you should have paid more attention to the title here. Such short and non-detailed topics arouse suspicion in me.
I understand the suspicion, especially with dApps. However, I implore you to give the site a try, everything on the site is done through smart contracts from creating events to settling events. There is absolutely nothing done within a database or backend server, just the display of the site. The only 3rd party intervention would be disputes and are handled by me, which should occur rarely.
On the site itself, there are detailed FAQ's to help you navigate the functionality much better.
https://app.defight.io/#/faq