There will certainly be interesting lessons to learn from this, especially as the crew got the aircraft back on the ground intact.
The crew would not need to know the Stansted ILS frequency. They could just enter EGSS and the runway in use as the alternate destination, accept radar vectors to the ILS, use the autopilot (with the rudder trimmed correctly on the A319) and fly the approach and landing. The database knows the ILS frequency and, if necessary, ATC knows it anyway.
I wonder if BA practise engine failures in the simulator using the autopilot? It would seem sensible to use it as you can on the A319, as long as the rudder is trimmed, but simulator base checks normally require manually flown engine failure procedures. Certainly the Kegworth incident may well have been different if the captain had used the autopilot instead of flying manually as per his training. It allows you to monitor the situation much better.