Q: The clutch lever that the slave cylinder pushes is not pushing/springing back

It sounds like you may have to replace the clutch. Clutches can fail in a number of different ways and exhibit a multitude of symptoms. Most people are acquainted with clutches that slip from simple wear, but it sounds like you may have a collapsed pressure plate or even some lining that has peeled off and gotten wedged in the clutch face. That takes all the travel right out of it. and would give you the symptoms you describe. But before you head down to the parts store to buy a clutch kit, I recommend you contact Your Mechanic to have a technician come to your home or office and inspect your clutch to be sure that it needs replacing.