Ericgkl, tech_sales;
Not sure if the following is helpful in explaining if damage to the IDG can progress upstream from the disengage solenoid into the IDG drive itself. At first blush it would seem that the unit or the installation would self-protect from such catastrophic damage but perhaps not.
From FCOM 1.02.24 (or thereabouts in others' FCOMs), Abnormals:
ELEC IDG 1(2) OIL LO PR/OVHT
– IDG (affected).................................................. ...................... OFF
If the associated engine is running, the IDG (integrated drive generator) must be disconnected from the engine at, or above, idle to prevent damage to the disconnect mechanism. Press the IDG pushbutton until the GEN FAULT light comes on. However, do not press for more than 3 seconds, to avoid damage to the disengage solenoid.
The IDG FAULT light goes off, when the IDG is disconnected.
One generator remaining on an electric airplane is a serious matter.
However, the A320 (as most know) has the 5 KVA Emergency Electrical Generator which is hydraulically-driven by the Blue system, and two 23-amp/hour batteries to run the hot buses which are supposed to keep you alive for 30 minutes through the TRs.
And then, so long as the airplane has hydraulics you can fly it on differential thrust, rudder and manual stabilizer trim. I've talked with someone, (FAA certification guy) who's landed the airplane using this method and he said it worked fine and was easier than the sim... ;-)
PJ2