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SuWt 2 is a planetary nebula consisting of a bright ring-like waist fromwhich protrude faint extended lobes - a morphology believed to be typical ofprogenitors which have experienced a close-binary evolution. Previousobservations of NSV 19992, the star at the projected centre of SuWt 2, havefound it to comprise two A-type stars in a 4.9 day eclipsing orbit, neither ofwhich could be the nebular progenitor. Radial velocity studies provided a hintthat the systemic velocity of this double A-type binary might be varying overtime, suggesting the presence of a third component hypothesised to be thenebular progenitor. Here, we present an extensive radial velocity monitoringstudy of NSV 19992, performed with the high-resolution echelle spectrographUVES mounted on ESO's VLT, in order to constrain the possible variation in thesystemic velocity of the A-type binary and its relation to the progenitor ofSuWt 2. The observations, acquired over a period of approximately one year,show no evidence of variability in the systemic velocity of NSV 19992.Combining these new observations with previous high-resolution spectroscopydemonstrates that the systemic velocity is also stable over much longer periodsand, moreover, is distinct from that of SuWt 2, strongly indicating that thetwo are not associated. We conclude that NSV 19992 is merely a field starsystem, by chance lying in the same line of sight as the nebular centre, andthat it bares no relation to SuWt 2 or its, as yet unidentified, centralstar(s).

On the possible triple central star system of PN SuWt 2: No m\'enage \`a trois at the heart of the Wedding Ring