Even the USB key .mp3 homebrew?

https://cani.rootmy.tv/?q=OLED42C2PUA at least here the one listed method for webOS 24 is patched.

What is the method you mention? A top google result seems to be [1], which says

> All release versions of webOS 9 ("webOS 24") are patched. This means 2024 models and older TVs that have been upgraded to webOS 9 will require another exploit such as faultmanager-autoroot [2].

and [2] says

> As of 2025-08-24, the latest firmware for essentially all LG models running webOS 5, 6, 7, and 9 is patched.

[1] https://github.com/throwaway96/dejavuln-autoroot

[2] https://github.com/throwaway96/faultmanager-autoroot