Thank you very much! It worked.PS> Ok I think I've sussed it out. 1st thing go to the end of time. Talk to Hestia, go into the wardrobe and click on grace. I think that even though you have Grace as your companion. If the end of time has been reset the game doesn't recognize it. Then go back to Salem 1969, step on the church she has the memory. Then back to 1692...
In my case, however, resetting Salem 1692 was not necessary (I had already saved the whitces and they appeared).
I only restarted Salem 1969.
I have to point out that I aready had the power unlocked following the path in the OP.