Shifter not engaging?

Okay, if you try to shift it without using the clutch does it grind in each gear? That would at least tell you if the internals were moving as you shift. Next would be if it broke a CV joint or axle it would act this way. The other things would be if something in the transaxle final drive failed. Anything registered on the speedometer during these tests? Not much in a manual to fail this way.

The idea of shifting it without the clutch is to see if the internal shaft and forks are moving. It would be rare for them all to fail. It could be that something like the input shaft sheared off, but I would expect some noises.

With it shifting the same way with or without the clutch and the engine running about the only thing I can think of would be if the clutch was locked over center, so it stays disengaged. Even with that I would think that the pilot bearing drag might spin it enough to generate gear clash. In this case it's acting like there is no connection at all. You might be able to get some feedback if you pulled the starter and looked into the flywheel area with a camera and to see what is going on with the clutch. Might help to look in there and have someone rotate a tire with it in gear and see if the clutch disc moves.

Okay, if putting it in gear and high revs did move the tires some, I would pull the starter and look at the clutch. It's not a normal failure but someone could have pumped the pedal a few times and the throw out bearing either stuck or the clutch might have locked up so that it doesn't clamp on the disc. You mentioned the master being stuck and that could factor into that as well. Something you might try, Loosen the bleeder screw on the slave cylinder and see if you get pressurized fluid out of it instead of the normal "leak" If the master was stuck in a way that doesn't let the slave release it might be the reason you have no movement. It could act as a one-way valve and is just holding the clutch disengaged. I think that the car uses plastic parts for all of it and maybe someone put the wrong fluid in and swelled the seals?
If releasing the pressure gives you back the gearing then I would err on the side of caution and replace the master, line and slave cylinders unless you have a way to test the fluid and verify what it actually is (Should be DOT 4). Wouldn't be the first time someone added the wrong fluid to a reservoir without knowing what they were doing? Had a car a couple years ago that the owner "topped up" the low brake fluid with engine oil. Ended up replacing the entire brake system because of the contamination.

Fork is inside the bellhousing, which is what the slave is pressing on. That is clutch material. Looks like it ate the clutch with all of that material on the inside of the bellhousing. Probably was slipping and they overheated it and the binding agents got fried and the lining shredded. I've seen that on race cars and on cars driven by people who have no business driving a stick. Think that one is about a 12 hour job to change. The automatic is about 10. They don't even show removal in the info I have, should be like the automatic but not sure if it has room to move the trans far enough to get the input shaft out or if you have to drop the entire thing out. I try to stay away from anything Euro if possible.