For experiments where the particles formed a half-torus geometry after poking, the particle's half-torus geometry was imported into COMSOL. In addition, the observed experimental flow time (exp,flow) was used as the time input for the fluid dynamics simulations (sim,flow). The viscosity was then varied until the simulated inner area matched the observation at exp,flow. For experiments where the particles cracked, we used a quarter sphere with a sharp edge as the geometry after the initial poke. The simulation viscosity was varied until the sharp edge of the moved by 0.5 µm (the resolution of the microscope). Since no flow was observed experimentally, the true viscosity of the particle must have been higher than the simulated viscosity, hence the simulated viscosity is a lower limit.