You have Ben Gurion's statement, pur and simple - no fake, no hidden meaning, no claims "in an obscure book by an obscure author" - that is what he said.

Do we?
All we have to go on is something on page 99 of some bloke's memoir that no-one else ever heard BG say, and which is contradicted by everything that he is actually known to have said.

But you have to cling to it because you have NOTHING ELSE!
Right Jim?

Beg Gurion was aware of the fact that they were seizing Arab lands

He was not because they were not.