How do we get the recipe for the tablet of power on isle of siptah?

It seems my friend somehow can craft this item from her inventory but I can’t. From looking up the information from the old map we had to go to the archivist in the unnamed city.

But where do we get the recipe from on this new map?

I got the recipie from a random drop.
Cant remember if it was a vault chest or world boss. I think it was a world boss.

I got 2 so far. Both from a vault (large chest).