On occasion during my Army posting to Ft. Shafter, Hawaii, I had the opportunity to interface with CILHI. CILHI being Central Identification Laboratory, US Army, Hickam AFB, HI.
CILHI, among other things, was responsible for retrieving and verifying identity of KIA remains from any and all American conflicts. Those guys trained hard on the cliffs and jungles of Hawaii and could go anywhere and get anything in their mission to bring closure to grieving American families. And often did.
Now, and in regard to this UFO issue, hearing or reading something went down in an 'inaccessible area' or is 'too hard to get to' does not wash well with me. Try again talking heads. IF they really wanted to get to it, they could.