If it’s the same bone [your cite says it was found in 2000; my cite talks about a bone found in 2002] then it was soaked. But if soaking means it was mummified, then all bones, including fresh bones, are mummified:
Q: As I recall, you soaked fossils in a mild acid to dissolve the mineral deposits on the inside of the bones. Why does the acid not harm or dissolve the vessels as well, but instead leaves them intact and pliable? Paul Moffett, Indianapolis, Indiana
Schweitzer: That is a good question. The type of acid we use is very commonly applied to remove the mineral from modern bone to reveal the structural proteins that are so intimately linked to the mineral. It is a very mild acid and is more accurately a metal chelator than a true “acid.” So it removes the mineral while leaving the protein intact, and it does not harm cell membranes or vessels in modern bone, so we hoped that it would not in our ancient material either.
http://www.pbs.org/wgbh/nova/nature/schweitzer-qa.html
“If it’s the same bone [your cite says it was found in 2000; my cite talks about a bone found in 2002]”
—It’s the same bone. It was found in 2000, and was excavated over three summers (summer of 2000, 2001, and 2002). And so it wasn’t until 2002 that Schweitzer got to experiment on the bone.
But it is the same bone.
As to your statement But if soaking means it was mummified, then all bones, including fresh bones, are mummified:
, I'll admit I'm a little confused. Why would that mean all bones are mummified?
Soaking the fossil doesn't mean it was mummified. Soaking the fossil meant all the minerals were dissolved but the protein stayed, which is exactly the same thing that happens if you were to use a fresh bone.
The interesting thing about this fossil, obviously, is that no one expected there to be any proteins in something 64 millions years old.