Hi, probably isn't the best solution, but if nobody else with anything better...
As your device is a miniPC, you could try to boot a live linux from USB and backup your data (will be on an ext4 partition, and look for the "userdata" folder, or anything else if you have). In this way you can check the hardware too.
Run the LE from USB (select "live" at installer screen), so maybe you can try first if the newer versions of the LE working on your device... If working in the live mode, try to install it and use the files from backup to restore your data.
Hint: if you don't want to rewrite many times your USB stick for different installers, check the Ventoy project. Working even with the LE image (I tried in "live" mode), just unpack the LE "img" file somewhere to the USB stick after the Ventoy installed.