How the heck did they get all the way from the ice-covered-mountains to the desert?!
and you know they didn't have any lodestone!
I just reread the series. According to New Blood, it took them three eights of days from they decided to go into the troll caverns, and find a water hole. That does make somewhat sense, taking that long. However the trolls should have discovered that pointy-eared filth was among them, in the shadows. After that, it takes not long before they are at the golden tunnel.
Then they are in the dessert, killing. Right after the zwoot stampeed.
Now, it takes three days to cross the dessert from the tunnel of golden light, according to the map. There is no way they could have gotten there so fast.