so i went for some google search, and here is what i found, as this affair seems to have many posts around, it may be good to collect them, here are some of them :

https://bitcointalk.org/index.php?topic=1600051.0
https://bitcointalk.org/index.php?topic=1046791.0
https://bitcointalk.org/index.php?topic=1415856.0
https://bitcointalk.org/index.php?topic=1051755.0
https://bitcointa.lk/threads/who-are-some-of-the-biggest-scam-artists-in-bitcointalk.473032/

So this guy is definitly related a lot of scam/hyips, now regarding bitdice, i think they should keep the funds untill their origin is prooved, if possible. If not possible, i don't really know what would be the best thing to do as i am not so aware of Australian laws.

Look at his LN account, especially the subscriptions https://www.linkedin.com/in/bitcoinandco/

edit: link update.

I think Alex should reimburse all the people this asshole has scammed, I don't even think the 38 BTC will cover up all the BTC he has scammed in total.