dWe know Luffy already have two of them (prints of them) and he will get the third in Wano. the fourth was in Fishman Island before but no more. we can assume that some had hidden it. but i really think Jinbe might have done that or just he has a print of it already. so assuming that is the case Luffy would not have to look for it in the first place.
Jinbe blieved in Luffy and planned to join him since MF, so it would make sense if he did that. I assume the knowledge that the RP was in Fishman Island was not a common knowledge to begin with Roger has his VOAT and his instincts, but i doubt anybody else knew that. so it is possible Jinbe hid the RP after MF somewhere in the depths of the sea. he is strategist so such a move is expected from him.
Jinbe blieved in Luffy and planned to join him since MF, so it would make sense if he did that. I assume the knowledge that the RP was in Fishman Island was not a common knowledge to begin with Roger has his VOAT and his instincts, but i doubt anybody else knew that. so it is possible Jinbe hid the RP after MF somewhere in the depths of the sea. he is strategist so such a move is expected from him.