Heck, last I saw Rick was thinking about turning over the black girl in exchange for keeping the peace.
That would be about the stupidest thing he could do.
The great thing about zombie movies is that the humans act so frustratingly and inexplicably stupid that it is great fun to think about how you wouldn't make the same mistakes if you were in their shoes.
One perfectly good example is how women are portrayed. Zombie movies always have the women fighting zombies alongside the men. Our political correctness demands it. Yet if there was a real zombie apocalypse and 95% of humanity was wiped out, we'd need the women to ensure we could have children and rebuild society. If the zombies wiped out civilization, the survivors would mostly come from remote locations, like offshore oil rigs, submarines, mines. Yet those places are overwhelmingly male. If 5% of humanity survives, and 95% of those are male, then women are the most precious resource in the world.
"What's that noise? I'll go investigate". Uh, no, send a man out there, they're expendable. No big loss if he doesn't come back. You stay behind the barricades.
bottom line, herschel should have given him the advice that since rick knows the guy can’t get past grudges, they can’t believe it will just all be over if michonne is turned over. hardly. he’sgot grudges against the whole group for their attack/rescue of glenn/maggie.
read the comic series for more insight.