The two-dimensional Shastry-Sutherland lattice (SSL) belongs to important models in the field of quantum magnetism as it combines low-dimensionality, geometrical frustration and strong anisotropy. Besides the insulating SrCu₂(BO₃)₂, the metallic tetraboride TmB${}_4$ belongs to its best-known examples. In this work, we investigate the development of TmB${}_4$ magnetization under magnetic fields (B) up to 60 T, applied at different angles with respect to the easy magnetization axis c. We aim to determine the extent to which phenomena associated with the SSL remain robust in high magnetic fields when the field is tilted away from this direction. Our results show that at temperatures (T) below 20 K significant deviations from the easy-axis interpretation of magnetization, in which the magnetic moments of Tm-ions are oriented only parallel to c axis, occur at deflection angles higher than 70 degree and in magnetic fields above 30 T. These values noticeably affect the corresponding B vs T phase diagram of TmB${}_4$ and point to a collapse of SSL phenomena under these conditions. The observed high field magnetization anomalies in TmB${}_4$ may also suggest the existence of new field induced quantum phases in this Shastry-Sutherland compound.