I’m really confused about the Sith Dagger, and need to figure it out before I can comfortably edit the parts related to it.

Ochi of Bestoon has the Sith Dagger. It’s referred to as an ancient Sith artefact, and he’s explicitly described as a collector of ancient Sith artefacts. He also used it to murder Rey’s parents on Palpatine’s orders, prior to Palpatine’s death.

But: the dagger couldn’t have been made any earlier than the destruction of the Second Death Star, because its shape relates to the shape of the fallen wreckage on the horizon, to reveal the location of the wayfinder.

How can it be ancient and also less than thirty years old?
Who made it, and why?
If Palpatine didn’t make it, because he was dead, who else knew the location of the wayfinder?
Why make a map dagger to begin with, instead of just taking the wayfinder? And if you want to leave it where it is, why would you make a map for other people to find it and take it?
When did Ochi kill Rey’s parents, if Palpatine gave the order but was also dead before then? (Rey is younger than Kylo, who was canonically conceived just after the Battle of Endor.)
How did the Sith Dagger go from whoever made it to Ochi of Bestoon?

The more I think about it, the more confused I get.