No connection to 74 engines. Qantas push 'em hard because of the route lengths and TO weights. Always were hard on engines.
RR knew of a fault with T970s back in summer 2009. They made a modification to engines on the line at Toulouse. They notifed Euro Cert Authority and they decided to monitor and not to stop operation.
Of the 80 T970 units in service over half already had the newer design. Qantas was left out of the information loop.
The rest is now history.