Disclaimer: Personal opinion, not speaking for my employer.
I am with you, and I hope that this will become more transparent this year with the *EU Pay Transparency Directive* coming into effect.
But I am not involved in this at my company, so I can not directly help you today.
https://de.wikipedia.org/wiki/Richtlinie_%28EU%29_2023/970_%28Entgelttransparenzrichtlinie%29 (German, unfortunately no page exists for this on the english wikipedia)