Complex sentence: Kresh's robot Donald, who heard of this incident, forced by the first law to act, contacts robots in the area to perform a search, and tells Dee that she is being lied to about the simulation.
Split into simpler sentences: Kresh's robot Donald, who heard of this incident, is forced by the First Law to act. He contacts robots in the area, who begin performing a search, and tells Dee that she is being lied to about the simulation.