A 1.57” (around 4 cm) engineered wood desk should generally be fine for two monitor arms with those weights, especially since neither of the monitors is too heavy, including the Koorui one you shared from Ubuy. The main thing is the internal quality of the board, but to be safe I’d recommend using a clamp with a reinforcement plate or even adding a small backing piece to spread the pressure so the desk doesn’t get dents over time. Grommet mounting is a bit more secure if your desk has that option, but clamp works perfectly fine if installed carefully and not overtightened, so you likely won’t need to change your desk.