To be fair to Vinten though, this sounds like either the camera & teleprompter wasn't balanced front and back on the sliding baseplate (easy to forget if adding a prompter to a previously balanced camera), and/or the balancing spring wasn't turned up to match the weight of the whole load, and/or the total weight was out of the spec of the head's balancing spring.
Vinten tilt locks really aren't designed to be "hard locks" taking the weight of an out of balance load. If it was in balance, it would just stay in place when the tilt lock is released.



