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Dual quasars at small physical separations are an important precursor phaseof galaxy mergers, ultimately leading to the coalescence of the twosupermassive black holes. Starting from a sample of dual/lensed quasarcandidates discovered using astrometric jitter in Gaia data, we present a pilotcase study of one of the most promising yet puzzling candidate dual quasars atcosmic noon (z$\sim$1.8). Using multi-wavelength imaging and spectroscopy fromX-ray to radio, we test whether the J0823+2418 system is two individual quasarsin a bound pair at separation$\sim$0.64'', or instead a single quasar beinggravitationally lensed by a foreground galaxy. We find consistent flux ratios($\sim$1.25-1.45) between the two sources in optical, NIR, UV, and radio, andthus similar spectral energy distributions, suggesting a strong lensingscenario. However, differences in the radio spectral index, as well as changingX-ray fluxes, hint at either a dual quasar with otherwise nearly identicalproperties, or perhaps lensing-based time lag of $\sim$3 days paired withintrinsic variability. We find with lens mass modeling that the relative NIRpositions and magnitudes of the two quasars and a marginally detected centralgalaxy are consistent with strong lensing. Archival SDSS spectra likewisesuggest a foreground absorber via Mg II absorption lines. We conclude thatJ0823+2418 is likely a lensed quasar, and therefore that the VODKA samplecontains a population of these lensed systems (perhaps as high as 50%) as wellas dual quasars.

Varstrometry for Off-nucleus and Dual sub-Kpc AGN (VODKA): Investigating the Nature of J0823+2418 at $z=1.81$: a Likely Lensed Quasar