The talk focuses on the shattered pellet injection (SPI) into tokamak plasmas affected by critical instabilities or crossing the safe operation space boundary (in particular, tungsten accumulation, density limit and vertical displacement event). The experiments at JET in 2022-2023 and plans for experiments (including the first results if achieved) for additional experiments at AUG are summarized. The modelling needs are highlighted. The effect of tungsten on the disruption dynamics can be modelled in INDEX to some degree, however due to the strong role of asymmetries and MHD instabilities, JOREK modelling is needed for better understanding. The key results include in particular surprisingly long pre-TQ times for some cases of injection into plasmas with significant W accumulation and hollow temperature profile. However, this parameter varies greatly, seemingly with dependence on the structure of MHD modes upon injection. Furthermore, apparent slowing down/stopping of a VDE by the SPI and further increase in radiation in injecting higher neon content pellet into a density limit disruption were observed. The plan for additional experiments on AUG is discussed highlighting the differences with respect to the JET experiments – thermal energy and triggering methods. In the unlikely case of early execution of the experiments, the first results from AUG will be also reported.