I don't think he went to Galatasaray to achieve anything serious but just to go away from Napoli who were bent on frustrating him. Osimhen going to Galatasaray is just a short term something and I expect that by January transfer window he will be considering moving to Chelsea that seems to be his preferred club. He will however, want to make some impact in Galatasaray as a great player, but he definitely will not be dreaming of winning any big title there.
Well, I was surprised that Chelsea didn't request him quickly for their ranks, but it's something that only they in Europe could explain, I have no idea what would have happened there, however this is something that the player is doing and even if it is in the short term for this team, if he does really well I don't think Galatasaray will let him go so easily, besides they are in a very good position, they are in the UCL and they can make the difference, what they achieved in the UCL was great, however this is the opportunity that the player has to show his worth, I'm sure that in this season alone he can show a lot.