Anyone who knew that leading the enemy straight to the doorstep of your friends and family is a colossally stupid move.
This is just silly. Anyone would head for the safety of the grove as opposed to dying and being eaten by goblins. At least there's a chance of living if you make it and get behind the gate. From there you can defend yourself.
In fact, the grove has been attacked more than once before this scene even plays out.
The idea of someone taking solace in knowing the grove's location is still hidden while getting eaten is nonsense.
And yes, the refugees have a lot of nerve. They're literally hiding in the grove for protection while the druids are complaining about their presence.
Aradin IS a blowhard. Have you talked with him in Baldur's Gate?
Nothing he says or does in Act III changes that he was right in trying to get back to the grove. And that Zevlor was wrong for keeping the gate--which doesn't even belong to the tieflings--shut. Kanon's death is on Zevlor. He let his ego and dislike of Aradin get in the way.