We have neither, except the root.xsi which is in the SDK, and the .scn files, which are the raw version of root.xsi
As far as I know, the original XSI's are more than 700mb of data, and I do not know of anyone that has them either.
We do not have the .car file, rather, I looked at the bone structure and added the PCJ's manually, and the scale is taken from the humanoid gla.
This method generates a new .gla file, which is then merged. When I compiled test anims with carcass using command-line (to force -flatten, just in case), it did not generate an animations.cfg file)
This project's purpose is to enable modders to add new animations to JK2's humanoid gla (and from what I have seen, adding new animations to JA will be even more straightforward). I believe there are plans to strip all the non-mp related animations from the .gla, but that will be done using tools made by Wudan. However as it is now, this project adds new animations, it does not delete any.