Try a fsck on the disk from your Laptop? Did you properly unmount/eject your floppy/usbstick?
Can you give me the uname -a of your laptop? (what distro are you using? Is it a current one?)
Maybe try a bootable Linux from CD and try reading it from there?
What about your usb in a Windows machine, and let windows checkdisk it?
did you try fat12?
doc
And this page talks about mkfs -F ufs but I'm not sure if that is a format both the Amiga and your laptop can handle. From:
https://amigaunix.com/doku.php/tips-tricks
Try a smaller USB stick? Maybe another USB stick does work?
There is a website that says:
mkdosfs /dev/sdXX -s 128 -F 32
Windows users can format with file explorer, select FAT32 and set the allocation unit size to 64K.
And maybe it might sound stupid to try, but mkdosfs has an -A for atari version, maybe it also works for Amiga AND on your laptop?
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Long filename-ish
The bug you see on screen is what I saw once. That fat only could handle 8.3 sized filenames, then Windows linked entries together to make longer filenames possible, but this corrupted the last two characters from a 8.3 filename, and machines that did not understand kept displaying the "filename" until a \0 null was found. But for this bug, you would see the start of your filenames, and in your example we see junk.
The Amiga allows long filenames (31 bytes long, by default, there are options with longer names) and your laptop doesn't know about that encoding?
https://en.wikipedia.org/wiki/Amiga_Fast_File_System
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What do you get on the USB stick?
try copy the partition to a file with dd, then reading the file with a hexeditor (or the unix command strings if nothing is available):
dd if=/dev/sdc1 of=MYDISK.img bs=1M conv=noerror
Do you see "fat" data at the beginning? (fat begins with the directories, not with the data)
For this method to be more readable, you can remove entropy from your disk, for example, when just formatted on your Laptop, fill your empty space with zero:
cat /dev/zero > ~/mnt/usbstick/justafile ; rm ~/mnt/usbstick/justafile
Make files with names like AAAAA and BBBBBB and try to find them with the hexeditor, maybe Amiga has a weird ASCII encoding?
If you can not find a hexdump, here is a perl one:
https://github.com/dreinhold/hexdump/blob/master/hexdump.pl
On debian systems, you need to "apt-get install bsdmainutils":
$ dpkg-query --search `which hexdump`
bsdmainutils: /usr/bin/hexdump