Slave cylinder, maybe more?

[NewArt]

If you're blowing the end out of the slaves, I would guess that the piston is over extending. This can be caused by a problem with the clutch release fork being bent or misaligned. Take a peek with endoscope or an inspection mirror to verify that the dimple in the fork is aligned with the centre of the mounting hole. If not, then you'll have to pull the transmission and check the fork retaining clip (pivot) and other parts. I discuss this in my video on my YouTube channel: https://www.youtube.com/watch?v=mfqpCgDGJhk&t=3s