I suggest you ask them why they hide those things. I know that their support team will glad to give clarification and doubts. Just give them time to reply or make a follow-up.
Well, I understand that you want transaparency but the thing is not necessary for me at all. Besides, if you have an account on their site you can simply take a glimpse at you dashboard, tracing back to your bet to see if you won or just loss because I believe it was been recorded as a form of transaction history.