Paul, Virgin Islands NP is one of two major parks largely created by donations from the Rockefeller Family. The other park is Grand Teton. The Rockefellers are not the only wealthy people who used their influence to lobby for the creation of national parks and monuments. There are others. And in most of these cases not all of the local residents were in favor of supporting these philanthropic gestures. In many cases the donors retained certain exclusive rights. And no, these rights were not always (if ever) extended to neighbors who typically found themselves subject to condemnation procedures.
This makes things confusing enough when this occurs in the forty-eight, somewhat less in Alaska and somewhat more in Hawaii. But territories are more confusing yet. The U.S. got the Virgin Islands from Denmark in 1916. They are classified as "an unincorporated territory of the United States". Most of the property boundaries were delineated under the "Danish System". The NPS has tried to maintain the integrity of those delineations to the degree possible, but as I stated earlier, records leave a lot to be desired.
Most significantly, the U.S. classifies the Virgin Islands as "non self-governing". The cities and towns are locally governed, but the federal government maintains a significant presence. The Park Service is not the only Federal Agency involved. As far as the feds deferring control, Congress has yet to approve a separate Constitution for the VI. So, federal agencies have de facto
control of law enforcement activities at their discretion.
That has very little if anything to do with survey law.