Once the tarballs are inflated, individual files with the asteroid names are available.
Their content is:

Column 1: DES minus ephemeris position in right ascension (DeltaAlphaCosDelta in arcsec)
Column 2: DES minus ephemeris position in declination (DeltaDelta in arcsec)
Columns 3-5: (ICRS) DES right ascension (sexagesimal, HH:MM:SS.SSSS)
Columns 6-8: (ICRS) DES declination (sexagesimal, +/-DEG:MM:SS.SSS)
Column 9: JD at mid observation time (UTC)
Column 10: DES filter
Column 11: DES magnitude
Column 12: uncertainty in DES magnitude
Column 13: phase angle (deg) (not a DES data)
Column 14: object's distance to the heliocenter (AU) (not a DES data)
Column 15: object's distance to the observer (AU) (not a DES data)

Note: The ephemeris positions are from the JPL. Their versions
are those from the time the file with the above pieces of information
was built.