Did these accounts have same cryptocurrency wallets?
Did all "my other accounts" also submit KYC / same documents?
Did all "my other accounts" also have deposits, if yes then how big?
Did "my other accounts" also win money in Metaspins casino?
Did any of the accounts managed to withdraw anything?
Did these account played same casino games?
None of these question were answered.
I'm not a gambling operator but I do own sites where I can trace visitors' activities and behaviors and the exact machine or device they've actually used and on what location usually latitude and longitude a lot of plugins can do this, a PHP site or WordPress site is very much different from a casino, one of the casino's script main features is an anti-cheat system.
I don't know how it worked but we all know casinos' defense that they have to protect the integrity of their anti-cheat to avoid cheaters from tweaking it since you file for mediation on 3 more platforms we'll wait for more updates until we come to conclusion on who's telling right but so far Metaspin has the edge.