Jelly 2E not able to get back to stock after bootloop

[yona-h]

When trying to flash my Jelly 2E with lineageOS I came across an error after the Flash Boot Image step (I did the unlocking and rooting steps before, it was already Android 12). The phone would get stuck in a bootloop saying it's in orange state, booting, rebooting again.

To get back to stock rom, I tried using SPFlash tool and the stock ROM following this guide: https://romprovider.com/unihertz-jelly-2e-firmware-stock-rom/ Afterwards I found the (official?) firmware and Flashtool from Unihertz at https://drive.google.com/drive/folders/0By1nhWOmuw2KdDhTUlFOZHpXQjg?resourcekey=0-KHJPIYVPw2iHL--cceWyaw There is also a pdf there explaining downloads, drivers and flashing.

I tried all 5 stock rom images (one from romprovider, 4 "official" ones), using SPflash and Unihertz' SPFlash. But whatever I try, it always seems to successfully flash the image, but when I start the Jelly2E, the screens keeps being black, with just a hint of the backlight. When I then plug it into my PC, the screens goes partially white with a vignetting "effect" and blinks that way, sometimes reversing the colors. I also get vabration feedback when touching the on/off or the home-button. No Fastboot or any text appears anymore.

Did someone have similar issues or even a solution to unbrick it? Thanks in advance!