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AT2022cmc is a luminous comma fast transient recently discovered by the Zwicky Transient Facility (ZTF). The combination of luminous (absolute magnitude -25) comma rapidly fading optical emission comma extremely luminous (> 1e47 erg-s) X-ray emission comma and self-absorbed radio emission comma do not neatly fit into the traditional transient classification scheme. We consider the most likely explanations for AT2022cmc is either a relativistic tidal disruption event (i.e. comma a star disrupted by a central supermassive black hole that forms a new relativistic jet pointed along the observer line of sight) comma or an exceptional member of the new class of fast blue optical transients (FBOTs). Here we request HST observations to allow us to precisely pinpoint the transient location with respect to the host galaxy nucleus. A nuclear origin would strongly favor a relativistic tidal disruption event origin comma only the fourth firmly established member of this class (and the first in over a decade). Alternatively comma an off-nuclear origin would rule out a tidal disruption event comma and instead favor either an exceptionally luminous FBOT or an entirely new class of transient phenomena.