You think it would be that easy anymore? After the change of policy on telegram app and you think such thing will be that possible and likely to happened?, Well to me i found it very hard to such thing to happened since telegram is no long a decentralized platform, and if such happens it can easily be revealed. However, there maybe another platform which such thing would happened about match fixing or even though its happening it would be with a serious caution.
Telegram has never been decentralised since it is controlled by a company. Decentralization is when a service or product is not under any central organisation and decision-making rests on different independent entities. Anyway, Telegram has just changed its policy of non-disclosure of personal information to government authorities. This entails that Telegram can give out information to users to the government if a court order gives such a judgement. Scammers will still look for other means to invade these limitations.