Tidus can't blame him - for wanting to look, even with Tidus's own failure. Esteban doesn't need to speak it, that 'if', but it's not his confession that bothers Tidus.

It's the apology. For dragging you into this. The state that Esteban looks, no different from how any of them look during this task, and he thinks he gets what Esteban is really apologising for, and it's nothing Tidus wants to hear - isn't what Tidus is trying to call him out on.

"You sorry you couldn't do this by yourself?" His hand is still resting on Esteban's shoulder, and he lets out a quiet breath, the mental dull yet buzz from dealing with the anchoring weighing down on his body. "That's my point, I don't want you doing this yourself. You include me in this - you're not alone, alright? We're doing this together. This isn't one person's burden to bear."