Try to understand the dealerships mentality: they get paid for doing work for Toyota when the car is under warranty. Replacing the TOB if there is a squeak doesn't mean the problem could have been the TOB. I have seen guys get their whole tranny replaced under warranty because the dealership can bill Toyota for the work. This is big business for them. The car service and repair business is full of scams and scrupulous characters.
There are several contact points that could cause this noise :
1. The TOB against the snorkel/snout
2. The TOB against the fork
3. The fork against the pivot
4. The fork against the clutch slave cylinder piston
Look at the bottom of page 4 of my build for images, but any one of these contact points could have been poorly greased. This seems unlikely to me, but it is worth considering because only the correct type of high temp grease should be used. If it wasn't used then the grease would melt under hot conditions, essentially leaving the surfaces bare. I would consider taking the car to a dealer or mechanic that will allow you to watch them as they separate the tranny from the engine, so you can see for yourself the condition of the system. If it was poorly or incorrectly lubricated then you have a claim for reimbursement, regardless of whether you are outside of warranty.
Also, I don't know if they used the new TOB (one with a white dot on it), but even if they didn't, I doubt you would be burning through TOBs so fast, so I don't think that is the issue.
Another possibility is that the snorkel/snout was damaged like mine was, but they didn't replace that, so the problem keeps coming back.
Lastly, and less likely, the fork could be bent or the pivot could be cracked. It has happened with OEM clutches, but it is far more likely to happen on aftermarket clutches, and as you can see from the pictures in the link below, the fork often cracks/fractures instead of getting bent, so this is a low possibility.
http://www.ft86club.com/forums/showthread.php?p=2874573