I think that it is a real stretch to say that the QF incident might be related to the US NAVCOMSTA at Exmouth Cape.
The recently released initial ATSB report says the incident occurred 154km west of Learmonth. That would make it about 170km W-S-W of the NAVCOMSTA at Exmouth Cape.
This is much further from the transmitter than inferred in reports on this forum.
Here is a ground track of the flight showing where the problem occured.
Had the flight track been directly overhead the transmitter then perhaps there may be some correlation.
Flynerd