good question, I think, maybe God does not intervene at all, (I do not believe these stories, how he helped especially JW being save while in the kingdom hall, while earthquake etc)
however, he sends his spirit to endure things, and will fix anything bad in the future/afterlife/paradise whatever...
I also always wondered, when there are experiences, where someboidy prayed to God for the truth, and he listened by sending JW there..ok, on the other hand, we say, that anybody, who does not pray to Jehovah in the right way will not be listened to...so, was this person a JW before ? hardly, so he must just have prayed to the wrong God (according to WTS) and still he listened....kind of contradicts itself..