CookieRun OvenBreak sequenced music files (.mid)

[KookyRawn]

The MIDI files in CookieRun OvenBreak can be playable in-game, but not in the MIDI player.
I tried swapping a regular MIDI file (flourish.mid for example) into the game, but the game couldn't play that song.

Maybe the CROB MIDIs are encrypted and they're probably FSB files in disguise in which they contain original MIDI files.
Each MIDI file in CROB starts with the number 7. The number 7 might be the first letter of the password.

Can you please help me on decrypting all the MIDI files in CROB? Here's a link containing all the encrypted MIDIs, including the soundfont file:
https://www.dropbox.com/s/qmw2p5xo5m8xwxd/CROB%20BGMs.zip?dl=0

MIDIs renamed into FSBs if they don't work: https://www.dropbox.com/s/2gd1q6eci6icrzt/CROB%20BGM%20FSBs.zip?dl=0