out of all the discs i could have gotten why those?

here is how to make a secret disk sound: get 3 jukeboxes, and those 3 disks. Then count to five, and put in disk 5. keep counting, and once you get to 11, put in disk 11. 2 seconds later, put in disk 13. Be horrified.

you can't even get disc 5 from a creeper.

Disk 5 was composed by Samuel Aberg and is obtained by collecting 9 "Disk Fragments" and crafting them all together as you would an ore block. Its sprite appearance subtlety mimics the color scheme of sculk, containing dark gray and highlights of a dark turquoise. The soundtrack lasts 2:58, and it takes a similar theme to Disk 11, playing sounds of a player doing various actions in a cave, sometimes overridden by sounds of seemingly corrupted audio.

it would sound worse if you played them all together.