Replaced ≠ fixed. Three symptoms do point to the harmonic balancer or tensioner but have you ever tested with belt off and warm engine already squeaking? You definitely want to isolate the source and I would try that for sure; ac belt off also.

A used balancer will be stiff when cold it would be impossible to tell if it's problematic. Do you have welding capability? You can weld the inner/outer parts of the old balancer and try it. Might be slightly noisier engine but without the squeak if that was the source

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2011 E70 • N55 (me)
2012 E70 • N63 (wife)