Welcome to FT
Fabry62 ^ .
I enjoyed your epic rant that was very entertaining, thank you!
A few points of confusion - why do you ask a flight attendant for an upgrade and why did you not confirm it upon ticketing

? That sounds like you made a handling mistake yourself.
And 2nd - why do you tell LH that you can buy upgrades on TK for cheap? That is exactly what they do not want to hear, so you have lowered your chances of a reasonable reply.
Not that LH gives reasonable replies .... but still, you gave it away there.