They’re paying for a private instructor…
And over the course of years…? The same exact unit with the padded issue?
Even if it’s an issue, someone that far along would know that’s the problem, the story doesn’t fit the details. You’re taught to inspect your instrument before and after every play, lube this every week, yadda yadda. There’s no way someone that good misses this obvious issue and blame themselves.
Pretty sure instrument maintenance is part of grade school music even.
How did any music teacher not hear how out of tune the instrument was. That story just doesn’t make any sense if you actually stop and look at the details. It’s made up bullshit.