ErikRookie
I have just tested this once again with my friends account while he was here. Did everything from scratch.. I invited him to a sub account of mine and tried to make a purchase online with a card of his that was attached to the shard sub account. The 3ds event was sent to me, the owner of the sub account, with no way to confirm it (Error, only the cardholder can authorize this transaction.). While on his phone no event came up. So we were unable to complete the transaction.