If the Ark was removed from the Kingdom of David, it probably happened when the pharaoh "Shishak" sacked the city. The Hancock version sez that Solomon's love child nonchalantly grabbed it and slid it right out of the country before anyone was onto him. And then the thief left it at Elephantine, for no apparent reason, where it stayed for (I think it was) 800 years, before it was removed to Ethiopia (again, for no apparent reason).
IOW, I think that it *isn't* in Ethiopia, unless it went there as war booty during the Ethiopian dynasty, after having been carried off by "Shishak".
There are those who think it was hidden, and that the details of its hiding place are themselves concealed in either the OT, or (according to at least one researcher) in the Copper Scroll.
IMHO, the most likely scenario is that the Ark was destroyed (the gold peeled off, the wood burned) when "Shishak" sacked Jerusalem, with a possibility that it was carried off as booty to Egypt. I don't think it was ever referenced in the Scriptures -- except in the past tense -- after "Shishak".
I have read (don't remember where) that the Ark is buried in or very near the Dead Sea...
Actually, it is, once obliquely, and once directly. It's almost certain that the Ark was in Israel as late as the reign of Hezekiah. In 2 Ki. 19:15 and Isa. 37:16, we see the king praying, "O LORD God of Israel, who dwells between the cherubim . . ." Such a title is always used of God in reference to the Ark of the Covenant, per Exo. 25:22, 1 Sa. 4:4, 2 Sa. 6:2, 1 Ki. 8:6-7, and 1 Ch. 13:6.
Further, in 2 Ch. 35:3, we see Josiah saying to the Levites, "Put the holy Ark in the house which Solomon the son of David, king of Israel, built. It shall not be a burden on your shoulders. And serve the LORD your God and His people." Therefore, Shishak could not have captured or destroyed it, since its location was known to the Levites centuries later, though they had evidentially removed it from the Temple at some point before Josiah's reign. Since Josiah knew that they had it, it seems unlikely that it had been missing for centuries, but had been removed relatively recently.
Therefore, the most likely explanation for the Ark's absence is that it was removed during the reign of Manesseh, Josiah's predecessor, and it was probably at this time that it was taken to Elephantine Island, where as you said it remained for several centuries in what was apparently a scale copy of the Temple in Jerusalem (we even have papyri asking the priests in Jerusalem how to properly conduct sacrifices--which only makes sense if those on Elephantine had the Ark with them). When Josiah took the throne and led Israel in repentence, he asked the Levites to bring it back. The Bible doesn't say that they did so.
Shortly after that, we see Pharaoh Neco coming up to go to war with the Assyrians at God's order (2 Ch. 35:20)! But Josiah continued to go after Neco in disguise until he was slain in combat. Why would he do this against someone who was siding with him against Assyria at the command of the God of Abraham, Isaac, and Jacob? While the Bible does not come out and say so, to me it seems likely that he was attempting to capture Neco to ransom him for the return of the Ark.
As for why the Bible doesn't just come out and say that the Ethiopians have the Ark, I suspect that was to safeguard the Ark.
Why would Solomon need a "love child?" He had enough wives/concubines, and subsequent children, to form a small village on his own.
Was Hancock saying that the Queen of Sheba & Solomon...? Solomon DID have problems keeping his robe shut.
"IMHO, the most likely scenario is that the Ark was destroyed (the gold peeled off, the wood burned) when "Shishak" sacked Jerusalem, with a possibility that it was carried off as booty to Egypt. I don't think it was ever referenced in the Scriptures -- except in the past tense -- after "Shishak"."
the curiousity of the possibility that the ark was captured was that it went wihtout a bang. It simply vanishes from history with nary a whimpler. It had clearly demonstrated offensive capabilities, and could have made problems that WOULD have made written contemporary records, if the experiences of the philistines are any guide when they stole/took it.
Reading about the ark and its various functions/actions is like reading science fiction in reverse - from the point of a bronze-age people dealing with an advanced artifact with various powers, some of which make more sense now (sparks between the 2 things on top of the arc smiting serpents scorpions etc) and others don't (parting water is a tech we cannot even hypothesize on).
Maybe its (or the items within which could not be touched)power source was depleted?
I can see why this artifact continues to hold fascination even today.