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The origin of giant planets and brown dwarfs discovered with direct imaging at wide separations (>10 AU) is challenging to establish because multiple formation and migration mechanisms are possible. The goal of this program is to determine the angular momentum architecture of systems hosting imaged substellar companions to constrain their formation and evolutionary history. We propose WFC3-IR time-series observations of three substellar companions spanning 10-60 Mjup to search for rotationally modulated photometric variability. Rotation periods will be combined with projected rotational velocities (vsini values) and orbit monitoring efforts from the ground to assess the geometric alignment between the orbital angular momentum vector and both the stellar and companion spin axes. Mutual alignment would point to a disk-based origin while misalignment will indicate an alternative route or dynamical evolution. To date comma only a single obliquity angle has been measured for a substellar companion we aim to broaden this to a larger sample comma paving the way for similar studies of lower-mass planets at longer wavelengths with JWST.