Error 7 while sideloading linage 23.2 on Xperia 1V

Despite carefully following the step-by-step guide, I still get stuck during the ADB sideload with error 7 (kInstallDeviceOpenError; Recovery: error in /sideload/package.zip).

I have triple-checked everything and downloaded the correct ZIP file for my device (Xperia 1V -> lineage-23.2-20260607-nightly-pdx234-signed.zip).

I also tried flashing the super partition with the provided super-empty.img, since this was not indicated in the guide. The 'wipe-super' command didn't work (error parsing), but 'flash-super' worked fine.

In recovery, my device appears as XQ-DQ72 instead of XQ-DQ54 but I don't think that is much of a problem.

Everything seemed to be working fine until the sideload error occurred.

Does anyone have any ideas?