Crew fuel management may not necessarily be the main issue here.
When the leak sprung, it gushed out, soaking the oil pipes, leading to oil temperature and pressure alerts. They spent a good 7 or 8 minutes dealing with that, consulting base etc. before clearing it. Once cleared, next message was "fuel imbalance", another hardly ever seen message. If no leak suspected, says manual, open crossfeed. They had recently checked fuel, nothing odd found, opened crossfeed and then the rest is history.
One oddity is that if the Fuel Imbalance warning is your first warning of a leak, the statement "if no leak is suspected" doesn't make sense (circular logic). Perhaps they should have done a manual fuel check ater that warning appeared (we don't know yet if they did or not as the official report is not yet out) but the manual nowhere states that this warning could be due to a fuel leak.
Another oddity is that the A330, despite automating almost everything except meal service, does not compare fuel remaining to fuel loaded against the rate of burn. Rumours suggest (anybody know for sure out there?) Airbus is adding this function to the automation now.