If we insured ourselves with a Spirit Rescue, would that be trusting and participating in our divine protection, or doubting it?

In a sense, it is both. This is unavoidable because the reach of the mind encompasses the spectrum of possibilities. In every blessing, there is an implied absence of blessing. In every curse, there is an absence of a blessing and a state of alignment with the Divine. So it is not faulty thinking or self-destructive to contemplate hazards and take active steps to avoid them, it is only being mature, and thoughtful, and planful to provide contingencies for such events. It is no different than purchasing insurance for a home in the event of fire or other source of destruction. Anything which has great intrinsic value needs to be safeguarded and the soul is no different. This will pay many dividends to be prepared in this way.