Clutch pedal drop on 1991 Audi 80

Back in January I was on a short road trip when my clutch pedal unexpectedly dropped almost all the way to the floor. There was still a bit of room, so I was able to continue on the trip and return home. The next day, I took the car in to the local Audi dealership and they informed me that the master and slave cylinders both needed to be replaced to solve the problem. I okayed the work, and one week later the car was returned working perfectly. At this point they also informed me that the brake master cylinder was leaking internally and would need to be replaced soon. That being a somewhat minor repair job, I told them I would take care of it myself. About a week later, the clutch pedal dropped to the floor again. All the way this time, with no warning. The Audi reps told me that the slave cylinder they had installed was faulty and would need to be replaced, which they did. Another week later, the same thing happened again. This time they told me that the clutch pin was faulty and needed to be replaced. This work was performed and the car worked fine for another week. When I looked beneath the car, there was fluid leaking from the area around the slave cylinder. This time, upon return to the shop, they told me that since the brake master cylinder had not been replaced, it was causing the clutch to drop to the floor and in order for the clutch to be fixed, they would also need to replace the brake master cylinder. I informed them I did not think this was the problem, as I was having no issues at all with the braking system, and I believed it was still either a faulty or improperly installed cylinder, either master or slave. I posted what had happened on an Audi enthusiasts website and they agreed that I was correct. They repaired the parts I wanted them to, and one month later the same thing has happened again. Could an internal brake master cylinder leak cause the clutch master and/or slave cylinder to fail with no effect on the braking system whatsoever?