I think Moses is trying to tell you that he really likes this place and he wants to make sure he is going to claim it, especially if a visitor comes. So he says it via the only messaging he knows how. Poop fence, pee marking - I think he's also saying a couple of other things; One - I am JOINING in the scent marking of some people so that I am seen as part of the place. (in the wild rabbits of a the same group will mark in one area to reinforce THEIR territory - so places that hold your scent, like furniture or linens, he may see as the group marking place.
TWO: " I am especially going to let certian members know that I am the dominant male here and so they need to know this!" This will include marking everywhere as well as on the back at the group marking place (furniture, linens)
Okay, so now you say...yeah, but what do I do??!!! Well, usually this will die down once he feels confident that he has made his mark. Literally. But you don't want to wait for him to destroy your furniture. SO, I recommend first shooing him off furniture, herding him back to his litterbox and just try Anitastarks method of spreading his scent via the damp towel. What this will be saying is, yes his scent is around, but you are the dominant bunny, and you claim this place and he is allowed to be where you want him to be.
If that does not work. Then unfortunately you will have to start from square one and that will mean limiting his freedom. (do you have an xpen?) This will at least allow a little more room during this time, plus as you slowly expand you can use it as a gate to prevent him from going to certian areas.
So you keep him there, and make sure he understands that is own personal territory by not reaching in take things out (unless he's out of there) And alllow freedom, but as soon as he marks, he goes back. Slowly allow more freedom as he earns it.
It really is amazing how a few days of bad habits can get ingrained and ruin months, even years of good habits. So if that is the case, you may need to go that route, but because he was trained before, I bet it won't take as long as it would if you were starting from the very very beginning. I'd estimate a week.
Keep us updated!