Polynglyphis tell the location of Weapons right? Thats how Robin found out about Poseidon, Thats how Robin found out about Pluton right? Then wouldn't robin needed to be included in all and every plots for the ancient weapons since she is like the only one other than their guardians who knows how to find them.
They have guardians that protect them like the Nefatari family or the Royal fishman family or even the Shandian warriors. Those warriors are the only people who know the polyglyphs. And the wg makes it apparent the the only two people that knew how to where or how to get them was franky and robin. And Franky doesn't know any more.
So to have not included in any plot dedicated to gathering the weapons without robin included makes the whole arc about the CP9 seem dumb and not realistic.
They have guardians that protect them like the Nefatari family or the Royal fishman family or even the Shandian warriors. Those warriors are the only people who know the polyglyphs. And the wg makes it apparent the the only two people that knew how to where or how to get them was franky and robin. And Franky doesn't know any more.
So to have not included in any plot dedicated to gathering the weapons without robin included makes the whole arc about the CP9 seem dumb and not realistic.