Interesting theories- some wacky, some far-fetched, some plausible. When the good LORD decides we should find it, it will be found.
I wouldn’t go anywhere near it. Only very holy hands should touch it.
It’s long gone, unless number 3 (/4) is correct; the Ethiopian claim is something that probably grew in the telling, and whatever underlying legend was there got lost since the Middle Ages with the Ark storied plastered over it. The other stories are ridiculous modern inventions (if one classifies the medieval mumbo jumbo of the Hadith as ‘modern’).