I tested it on my Windows 10 computer and all the tracks did sync on the newly formatted USB.
It’s very odd that it works on my Windows machine but not on the mac.
One difference I noticed is that on the Windows Rekordbox, the sample rates of all the files are populated correctly at “44100 Hz” and the bit rate of variable bit rate files are listed as “VBR”, while on the Mac Rekordbox, the sample rates of all the files are populated as “0 Hz” and the variable bit rate files list the bit rate values. Once I re-analyze, the sample rates are correctly populated and the variable bit rate files state “VBR”.