Tidus gives a nod to Ignis, and with that said he starts to turn, but not without parting words. "Well, I'll see you both ground side."

So he does catch Prompto's wave, gives the guy a quick lift of his hand in return. But with that, Tidus will leave them to go search out for his friend--who maybe he can convince to come with him, this time round.

(Narrator's voice: He did not convince her to go with him, but instead lost 5 relationship points.)