For what it’s worth, they have accepted my TransferWise debit card for the initial investment. On the other hand, they told me they would not accept my TransferWise UK account as a reference / withdrawal account.
Limiting withdrawals to bank accounts in the investor’s (or player’s) own name is common security practice for brokers (or internet gambling sites). So are restrictions on source of incoming funds, especially when operating with limited face-to-face customer identification.