With the pedal depressed the clutch should be disengaged, it doesn't allow the engine to engage the trans in movement.
With the pedal released the clutch is engaged and it is allowing engine movement to engage the trans and move the shafts in the trans.
With your pedal depressed, it sounds LESS nasty, but still nasty.
With the pedal released the clutch is engaged and it is spinning the input shaft, and that sounds really nasty.
It's either going to be at the clutch parts in the bellhousing (trans removed from car) or it is going to be something in the 5th housing of the trans with the actuation finger and throw out bearing and related parts but my money is on clutch parts damage.
Either find a local shop to do the work and get a rental, or get a rental and haul the MK2 home or have it towed home.