Each of the nine octads of the seventy-two is assigned a governing archangel: Metatron, Raziel, Tzaphkiel, Tzadkiel, Khamael, Michael, Haniel, Raphael, Gabriel, following the sephiroth from Kether downward.
The column has a mixed pedigree and it repays unpacking.
Michael, Gabriel and Raphael are the best attested. Michael and Gabriel are named in the Book of Daniel; Raphael is named in Tobit. All three are firmly established in Jewish and Christian angelology by late antiquity.
Metatron belongs to a different stratum: the Hekhalot literature and the merkavah tradition, where he is a figure of exceptional standing, sometimes identified with the translated Enoch. The name has no convincing Hebrew etymology, and its origin has been argued over for a very long time.
Raziel is associated with the Sefer Raziel ha-Malakh, a compilation of magical and cosmological material with a complicated medieval textual history.
Tzaphkiel, Tzadkiel, Khamael and Haniel are principally known from the sephirothic scheme itself, and are attested most clearly in the Kabbalistic and later magical literature rather than in earlier sources.
So the column mixes figures from the Hebrew Bible, from the Apocrypha, from Jewish mystical literature of late antiquity, from medieval magical compilation and from Kabbalistic systematisation. The nine of them are made to line up with the nine choirs of Pseudo-Dionysius, a Greek Christian text of around 500, and with nine of the ten sephiroth.
This is the pattern throughout the apparatus around the seventy-two: a coherent final table assembled from components of widely different date and provenance, presented without any indication that they differ.