After rereading the spoils....ive realised one thing.
It never said Aramaki gives up on going after Luffy. It says "Aramaki gives up". Which could mean a multitude of things....most likely implying him just ditching Momo and the scabbards after sensing Shanks.
At first I thought the spoilers were just misinterpreting a vague manga chapter. But the spoilers themselves are vague as heck.
This could chapter could very well show Aramaki leaving Momo and Co., but not hinting at him leaving or running away from the Island at all. He could go after Luffy or Shanks.
Meaning Ryou got unjustifiably shat on for no reason.