Please start with rereading over again here linked instructions: Flashing to Byzantium - #4 by libwood.
Now check (apt list ...) if bellow packages already installed, if not:
sudo apt install build-dep python debos bmap-tools f2fs-tools
sudo apt-get build-dep build-essential
sudo apt install python-is-python2
sudo apt install git
sudo apt install python3-jenkins python3-tqdm python3-yaml
And this one is the one that you are looking for, the one that should help you, I think:
sudo ./scripts/librem5-flash-image --udev
Usually I do forget something, but is it uuu -lsusb providing needed output? I hope so.
EDIT: Another simple, yet very important, post: New Post: Reflashing the Librem 5 - #31 by fagus.