I DID follow the tutorial. No disc was inside and the tray was closed. Not too hard. The shown model type in the flashing tool was also different after the process so it obviously worked. This is the current Data from MakeMKV:
Drive Information
OS device name: /dev/rdisk21
Current profile: BD-ROM
Manufacturer: PIONEER
Product: BD-RW BDR-UD04
Revision: 1.14
Serial number: CIDL505512WL
Firmware date: 2020-06-15
Bus encryption flags: 1B
Highest AACS version: 48
LibreDrive Information
Status: Enabled
Drive platform: RS8A10
Firmware name: PIONEER BDR-US04
Firmware type: Original (unpatched)
Firmware version: 1.14
DVD all regions: Yes
BD raw data read: Yes
BD raw metadata read: Yes
Unrestricted read speed: Yes