Ok! Ok! I found the problem, The quest says you need 15 gasoline, but the script it's just checking if you have more than the value, so with 16 gasoline or more in the shelter storage it will work fine.There is 15 gasoline in shelter, i thinked first too that he has all only in squad but then checked it again.
It might be that some reason game doesn't like that there is any in squad and all should be storaged in shelter?
public int gasNeeded;
gasNeeded = 15;
if (database.saveDT.CCD.arsenal [0].squadResources .itemQuant > gasNeeded) {
return true;
}