Zevlor talks to people and says, "Hey. This whatever-he-is just saved the grove. Treat them well." So people will, in general, not reject you at the grove.
This is allready happening ...
By wich i mean that Zevlor allready claims that he "make sure that people know what you did" ... but then he justa walks into his cave, and they all know somehow ... wouldnt be too bad, if he would at least stop by some guard, send kids to tell everyone, or yell at them.

You know, for the sake of immersion.
Personaly i still find it insufficient ... but acceptable.
Maybe i suffer from certain prejudices, but imagining myself in Tiefling situation ... my dream reaction would take under concideration this:
Im a refugee, weaponless civilist, who dont really know how to fight, i have all my sorry belongings here in single bag and there are lots of orphaned childern around ... i allready lost lots of my friends during my travels, and people who are keeping us here (druids) are trying hard to push us out threatening that we will be killed uppon ritual completition ... and outside (as our leader tells us) certain death awaits us ... so im basicaly scared as fuck.

Now bunch of monsters attacks our gate ... some random stranger helps to push them back, even tho they attacked him and his group aswell, so its quite possible that he was simply defending himself wich accidentaly helped us.

And then i find out that this stranger is a Drow ... character that is known to walk on surface only to kill, plunder, enslave and torture ... i dont even remember if i ever heared about single thing his people ever did that wasnt horrible ... my leader says that he is cool, bcs he just horribly murdered bunch of goblins ... dont get me wrong, im not against murdering goblins, maybe i even feel kinda gratefull that he did that, but still hes a Drow.
And for the sake of argument, lets say that he is baring mark of Lolth (red eyes) and openly admits in conversation with others that Lolth is still his godess.
So im certainly cautious around him, dont feel good when he is talking to me directly ... i wouldnt send him away, im too scared to dear that, but certainly would preffer him gone ... so i most certainly WOULDNT talk to him like a friend about my dream house, job and cat in the city ... i respond to his questions, briefly and straight to the point ... and then hope he would leave me be and its quite possible it would be clearly seen on me.
Same goes with everyone else ... to certain extend.

For example: If you play Dragon Age: Origins ... there is one rally racist Dwarf in Orzammar, that keeps complaining about you no matter what you are (unless you are Noble Dwarf) but if you ask to see his merchendise he simply states: "I take your gold, you are good enough for that."

And i LOVE IT!

Come on. They had children and every single freaking person in the grove at one point following animals around. They can have one or two characters who don't trust you following you around because you're of a race they don't approve of. I don't think that'd be a particularly challenging or time consuming thing to implement. A few characters with a few mean dialogues based on your race tag, and some characters maybe trailing you to "make sure you're not doing anything bad" wouldn't break the game - or at least I'd think it wouldn't.
Thats exactly what i said aswell.

+1!