Here's how I think they could implement the current mini-camps into the game:
You're on the beach. You're exploring. MOST people are going to find the Waypoint right outside the crypt entrance.
Now, in my fan fic, I made the main camp near the Dank Crypt, just to the east. Follow a small path hidden by bushes around the east corner of the building and you will come to the campsite. Made the most sense to me. However, I've looked a thousand times on the map from various angles. There's nothing but sheer cliffs there.
Although I think it would be awesome if they actually put the original camp right there, as I put in my fan fic, the easiest implementation of the original camp is, unfortunately, to make it a place not actually on the map that you teleport to via the Netherese Rune right there on the beach. It's some place nearby, but it's cut off on all sides. There's no real way to get there except by boat or by scaling the sheer rock walls.
BUT, if they're going to do that, they need to have a nice little cutscene. Instead of just, "This place looks as good as any," line, they need something more like:
You step up to the Rune and touch it. The symbol reacts to you for some reason. You have no idea why. Zap! Suddenly, you find yourself in that small ruined partial building across the log within the original camp. Looking around, there's another rune there against one of the walls. It just ported you to the campsite. Then you explore around and say, "Looks like there's no other way to approach this area except by water or by scaling those walls. Seems pretty safe. Maybe we could use this as a safe campsite."
Then, at least, there is a solid, immersive explanation as to why you can't find it on the map and why it is SO safe.
But then, no one should be able to find you there. Only those who are in your party can go there. Why? Because you are special... or maybe because you have the artifact... or whatever.
Either way, the original camp could be explained like this, but the celebration should be done at the grove, then. Not at the main camp. Grove makes more sense anyway.
As for all the other mini-camps, a door or doorway or something in different places could be added to the game simply by deleting a section of a wall and adding a doorway there. Then, to access the mini-camp, you walk up and trigger the doorway. Boom. You enter the mini-camp.
So, Dank Crypt? Put a new doorway in the hall between the two chambers. Doorway leads to the mini-camp they made.
Owlbear cave? Put some sort of extra cave-looking opening somewhere near the Selune Shrine. Boom, takes you to the owlbear mini-camp.
Stuff like that could be done for just about EVERY mini-camp they made so players feel like they are actually going to a real place in the game world without having to totally chuck all the mini-camps they worked so hard on.
And again, I think it'd be fun to unlock them. See how many you can actually find in the game. Then make each one unique and decoratable. Take stuff from one camp and put it in another that you like more. Whatever. Would add a bit of personal customization for those who like such things.