Transact Payments Malta Limited is a financial institution duly authorised and regulated by the Malta Financial Services Authority, registered under registration number C 91879. Transact Payments Limited is a financial institution duly authorised and regulated by the Gibraltar Financial Services Commission under registration number 108217.
Simply put, TPML (EEA) and TPL (UK) are the issuers of your Moss cards.

Only TPML/TPL can access the account, and may only do so to the extent required for settling transactions you performed with your Moss cards.

Simply put, yes, your funds are safe with TPML and TPL.