Him returning to the Celestial temple later on would explain Sam's lines.Why, we don't know if he returned back to the Prophets when his time with his family came to an end.
He may have eventually returned to the Celestial Temple and SAM is just conveying her thoughts to him.
However going back this interview:
Tawny: "Everyone knows the story of Mr. Brooks asking the showrunners to add that line into the finale of Deep Space Nine where he said that he would come back for his family. Okay, that tells us as future writers, we have to assert that he did indeed come back, and we should have Jake himself say it, and the legacy that he leaves behind is one of love and one of just incredible sacrifice for his family and for the franchise, and in a meta way, that’s the same legacy that the character’s legacy is the same as Mr. Brooks’ legacy"
If that was the intent, why did they literally have Jake turn the pages of the book to an empty field on Bajor and have him state that Benjamin never finished building the house?
Sure, it could be that he returned and simply never completed the house, but why be so ambiguous about it? In my opinion they needed to be a bit more deterministic here.
