I had the same problem, replaced the master/slave and no change, nothing broken...
so one weekend got it up on ramps and removed the box to find out 6 of the 9 bolts holding the pressure plate on where pretty much coming out..
so the plate was on the piss and not being able t o dissengage the clutch...
you can tell if the fork/ball is broken/bent anyways though the inspection hole... generally..
hope this helps narrow it down.