Are we sure that this was the old Idena? Maybe it was only a clone and they are only using the name Idena to attract people on their hacking attempt. I don't think a legit project will ask for our sensitive details such as our private keys. It can also be an attempt to destroy the reputation of the old/original Idea but their team can always confirm it here.
Idena always have used the same authorization method. More over on our betting platform we never ask to pass your sensitive data as you can see first the system forwarding you to the official wallet web-application which generates a special security token for you, more over your bet transfer is also happening on the side of app.idena.io. So, we never ask for any sensitive data. More information about auth. mechanism you could find here:
https://docs.idena.io/docs/developer/desktop/sign-in/A KYC can be a good solution for it but they aren't requiring it. Instead, for them to verify that we are a real human we are only required to pass a captcha challenge. About the games, they said it was on-chain betting, so maybe all works in automation like on how on-chain betting sites work on the past. But there must be a way to verify if the games are fair or not.
What for would you need a KYC in case if you know that real people gonna verify the result of the match and if you know that in any result of the match the prize fund would be splitted as it was originally confirmed via smart contract? I would think that you don't understand how actually IDENA works and it would be better for you to go a bit deeper into the topic of the idea of IDENA blockchain. I dare say that for now your arguments don't have much sense, more over it sounds more like accusations without merit.