Inconsistencies (or bad memory?)

I’m reading GEoD now, the new Duncan ghola was just introduced to Leto. Two things stood out to me as potential inconsistencies:

- Leto says “I am all of Atreides”, to which Duncan replies/thinks “Paul said something similar once.”

- In the same dialogue Leto says something like “… the last time we were in Sietch Tabr together”

If I remember correctly the original Duncan died at the end of book 1, having not had seen Paul basically since Leto I died. So in Duncans last memory of Paul, he couldn’t have known of his prescience, and he definitely didn’t go to Sietch Tabr with him in the first book.

So, do the gholas have reawakened memories of the first Duncan ghola, or his original body which died in book 1?