Why would he risk to open multiple accounts if we won multiple times at Sportsbet
and if they hold over 18k on his account?

And why they didn't contact him before that regarding this 'multiple accounts' issue?

It is also strange that they don't allow him to complete KYC verification...

We need more proofs here, and I will stay neutral for now,
but I asked legit questions, and I can understand the guy.

Stay calm and talk again with Sportsbet team.