You play 4e, don't you? That's simply not true in any other edition.
The question of what this scroll is, how the gypsies know about it and what they want with it - is indeed worrying, and deserves further investigation. Whether a first-level peasant with a full-time job caring for his own family is best placed, or even remotely qualified or equipped, to undertake that sort of investigation - is another question. At that point, my LG Fyodor would probably enlist the aid of the village mayor or priest or whatever authority figure they have, to handle the negotiations.
And now, incidentally, you're positing that these supposedly-true-neutral gypsies are performing acts of extortion that involve, potentially, letting a helpless man die purely as a negotiating tactic, when they could save him at zero risk and minimal cost. That should certainly be brought to the attention of the aforementioned village authorities as an issue in its own right. (After all, according to the rules of the settings, there's at least three Dark Powers checks right there - Extortion, Theft and Betrayal. For a healer to demand that a good person perform an evil act in exchange for his services definitely qualifies as 'betrayal of trust'.)
Interesting. When you were first describing 'lawful good' Fyodor, you said he was inspired by the gods. Now 'true neutral' is apparently policed by fear of the 'dark powers'. You seem to assume that all motivation is extrinsic. In your account, even 'good' Fyodor isn't really acting out of compassion, so much as a desire to please the gods.
My idea of LG Fyodor would still pick up the hobo and get him to the healer - if humany possible - even if he'd never heard of either gods or dark powers, simply because it's what he'd want someone to do for him if their circumstances were reversed. The fact that the stranger in your example is rich - opens up a whole raft of possibilities that the good deed may pay off later, but those are really a distraction from the 'alignment' question. "Doing good to please the gods (who may reward you, in this life or the next)" is really no different from "doing good because you expect to be paid", which (I think) most people would agree is closer to Neutral than true Good.