Unless he has a warrant on him, I expect the challenge will be what to do to keep him out of there. I think Pico camp is on private property. The AT was relocated downslope away from ski area property when a prior owner of Killington bought Pico and had grand plans to substantially increase the size of the resort by expanding Killington over to Pico. The ATC made the best of it and ran the relocation down slope on the west side through a nice but not particularly interesting patch of woods (green tunnel) ended up downslope from the Inn on the Long Trail leaving a big PUD. Many folks still hike the old AT route along the ridge line to Pico Camp and I expect the current owner of Killington and Pico could care less as long as they have control over the property. The prior owner with the grand plan, Les Otten is now focused on the Balsams in NH and planning to build the "biggest ski resort in the northeast" (by acreage as the local peaks in Dixville NH are much lower).

I am not aware of GMC having any rules on occupancy of their shelters and do not have any way of enforcing them even if they did. Most small towns in that area have zero law enforcement and depend on the state police and they are understaffed and tend to stay near their cruisers, Coincidentally I spent a night at Pico one night with a thruhiker who the day before had found a dead hiker in his tent at a shelter site south of Killington and he was quite surprised as to how long it took state police to respond to the site. He called 911 and reported it and was told to stay there until the state police responded and they kept asking him for an address. Eventually he borrowed a map and got a road name for the closest AT crossing and basically had to lead them to the shelter site. About 4 hours later a state trooper shows up in full state trooper gear with a smoky bear hat obviously out of his element. He interviewed the thru hiker and asked him for contact info which he did not have as he had used the dead hikers cell phone to make the call (this was 20 years ago when cell phones and towers were far rarer). VT did not even have any agency in charge of S&R until about 15 years ago when the state was sued for not responding to a lost skier who I think died. Up until then, the state depended on ski areas employees rescuing lost skiers, giving the ski areas the option to bill out of bounds skiers.

My guess is the GMC or the state will eventually apply enough pressure that he will move on to a spot with less resistance. Unless things have changed, there is or were shuttles up from Rutland and Rutland is a known town large enough to have social services to support voluntary and involuntary homeless individuals. Therefore, this individual may find Pico Camp to be a good spot to hang out, out in the woods but not that far away from services and possibly good picking from car parked in the former AT lot across from the Inn at the Long Trail. In most of VT, people with issues tend to gravitate towards the larger cities with services. In Burlington, the city elected to "defund the police" and the result is shoplifting, property crimes and minor offenses like this individual may be doing are effectively ignored.