@ailonn, as first thought of mine or another conscious approach, as based on @irvinewade post, please remove your microSD (if inserted) temporarily away.
My second thought here is that using shorter/another USB Type C cable will provide more current/power if your PC/laptop USB port (as mentioned in above post) doesn’t provide (through particular USB-C cable) at least 0.5A (just my guess, perhaps ensuring 5.0V/0.6A from currently used USB port is even better) to your Librem 5, therefore please connect your laptop (if perhaps older type) to its original power supply (should help) during usage of here related procedure.
I’d agree with @dos expert advice as positive and encouraging that you’ll get there eventually, that we hope that you’ll get there, that Jumpdrive will mount your Librem 5 eMMC drive soon. Therefore, and in addition, ensure usage of correctly extracted archive and, please, download this one (again and although the very same 0.8 version one), unpack it to another folder, with another name, and try here related procedure again from that new folder.
Also, after executing: lsusb | grep 8M, by having constant red LED light on, please do not disconnect (if so) USB-C cable from your PC/laptop. Just press Enter-key after typing: sudo ./boot-purism-librem5.sh.
As well, did you try: ./boot-purism-librem5.sh without sudo? Thanks for your feedback!