Here's the Disk Management in the 8500:

#3 hd
https://postimg.cc/nj3vVyvt

original hd

https://postimg.cc/xXGN1r2F

but I don't see how I can compare #4hd if it
won't connect other than to put inside the 8500
itself?

I also have the unknown hd which may or may
not work in the 8500 or 780.

I think at this point we could try putting in #4 in
the 8500 and run the Rescue CD and repair its
boot menu if possible because you said every hd I
attached after I changed the battery would be corrupted.

If that doesn't work I suggest we try the unknown
hd in both computers to check it. Starting with the
8500.

I just find it hard to believe changing the battery
caused all this and stopped our cloning dead in it's
tracks after all the work we've already done.

Thanks for the VLC link,

Thoughts/suggestions
Robert