I think you might be the one who's living in an alternate universe because who in their right mind would pay TWO HUNDRED GRAND for an early assembly of one of Michael's least well-recieved albums? And on a format that requires a similarly-expensive player and an equally-expensive digital-to-file transfer system to hear without running the risk of deterioration.
At this point your target audience has got to be your personal buddies because as it stands, that price tag is killing the tape's ability to be sold. If you truly want to let it go, then lower the price to at least 80-90k, if not 50-75k*. The listing as-is has stood there for at least five years, the fact that no one has come to scoop it up is not a good sign. And not to mention: DAT tapes have a limited shelf life. It's only a matter of time before they start deteriorating, and 9 times out of 10 when parts start getting lost over time, that's it. No chance of restoration. Again, not a good look for your "one-of-a-kind" item.
Not even gonna mention that last line, that ellipsis gave me flashbacks to so many keyboard warriors who used that style of typing to sound "totally kewl, dude!"
*I'd go as low as 10k, but I have a feeling you'd have a conniption fit.