People talking about the Talk no Jutsu possibility are just in denial of what Oda could do here. I'm guessing many of them are powerscalers.
I can see Oda doing some bullshittery with Raizo + Shinobu + Momo powers to get Ryokugyu out of the island
I can also see Akainu calling him back for some urgent business
I can also see Shanks interfering and telling Ryokugyu to fuck off
That's all i can see happening