Hello everyone!
I'm having trouble with the walkthrough!

It's the 4th mission, I found and escorted Arantir, gained the soldiers' respect, went to the witch and accepted the quest to find the sand, in general, I captured the entire map, even unlocked it at the cartographer's, but there's only 1600 grams of sand, and I need 10 kilograms, what should I do?
There's a prophet left on the map, whom my Alaric says he just passed by, nearby there's an archmage who warns about danger, and there's also a scout with a mage in the forest, but I can't reach them because the trees are in the way, so what should I do? There's no sand)
Something is glowing near the Necropolis, but I can't get to it either)
In the Sanctuary, they say that there's nothing there yet)
Should I just build up my army? I've already wasted a day, and I'm afraid that Fenef's legion is too strong for me)

Added 2 minutes ago
There's also a save where I helped the Necromancers))))
But I don't want to go through the huge map again)
And I don't think that will increase the amount of sand)
I also read here about some new soldiers, but I don't have them for some reason, and it's not that important anyway)