I can't comment specifically on this members case as I have no way of knowing who they are, but generally, a withdrawal will always be paid back to the most recent method used to deposit or the method in which the funds that were used to win originated from.
And again this isnt always the case as in some situations it isnt possible to pay back to a previous method, like if the deposit was prior migration and no skrill deposits had been made since.
@QueenOfAces , if you have only ever deposited with Skrill or your most recent deposit was with Skrill and you're still being advised to use another withdrawal method, please drop me a PM with your registered email address.
Conor