The best approach is to complete the Sokokar Timeline first. An artisan version of the sokokar series requires minimal gathered materials. After you complete the sokokar series, you can travel directly from Teren's Grasp to the Fens and use the sokoar to complete the quest too.
The Fens is a dangerous place if you're a low level adventurer. If you bring an escort of high level friends along, you'll have a much easier time with this quest because they can remove dangerous obstacles. However, if you're friendless or just have a deep desire to defy death, the quest can be done solo (even if you're low enough that mobs see through your invis).
There are occasional spots where a mob in the grass will wander close to the road, but you should be able to wait for them to move, or run just past the far side of the road to avoid them. When the road ends, cross the river and then time the rest of your journey, waiting for monsters to separate so you can run between them.
The first cache is up along the road toward Bathezid's Watch. Keep an eye out for roving Bathezids, and you'll have no trouble.
The second crate is east along the river. Stick to the road as best you can. There are rhino-riding Rilisian sentries on the road, so you'll need to find empty pockets between monsters near the road so you can run past the road guards. When you get near the Rilisian's bridge, you'll see a little path on the right that continues east along the river. Take that path. When you get near the crate, you'll need to be observant about where the monsters are. You may need to go a bit too far along the path, and then work your way back toward the river and the crate, in order to find an opportunity to get between the monsters. If you try to go straight up to the crate, you may discover that the monsters just won't give you a chance to get there safely.
Crates three and four are the same kind of thing: follow the road, and when you get close, look for a place that's wide enough to sneak past the monsters. It can take a few minutes to get an idea of where the open areas are created.
