The gear was certainly down the second time as the video clearly shows. So I cannot yet see any evidence that it was unserviceable or that it was not down the first time until it was selected up on deciding to go-around. By not properly engaging TOGA the engines would not spool up and the flight director commands would not provide guidance. The aircraft might then sink low enough to strike the runway. We don't yet know that is what happened, but others have got close on previous occasions. Nothing is sure, but it would fit with what we do know so far.