but the file has this in it boot=UUID=1510-0002 disk=UUID=1d2456fd-f3e0-4c17-b0ad-8bc237d5b0cf quiet
nothing is working
That's the correct default content. You have to add parameters that way: Click!
Here is a syntax description: https://www.kernel.org/doc/html/latest/fb/modedb.html
As you can see, cmdline.txt has a totally different syntax, compared to config.txt.