I hope this helps as I have read that they do not always spawn exactly the same place for everyone. I was driving from the NE corner of Oasis where the other Radio EDF attack happens towards the High Importance Target in Oasis which is literally to the left of the safehouse. As I was getting closer to the road to the safehouse, it notified me then. I had driven that way previously so I do not know any way to spawn it other than just aim to get the NE corner EDF attack out of the way first. That one spawns from the very NE road coming from Badlands.
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