Complex sentence: He valued a prostitute over his grandkids as demonstrated in "Guess Hoe's Coming to Dinner" where he brought the prostitute to Red Lobster and left the children with fishsticks, not believing that she was a prostitute until her pimp comes to pick her up.
Split into simpler sentences: He valued a prostitute over his grandkids as demonstrated in "Guess Hoe's Coming to Dinner" where he brought the prostitute to Red Lobster and left the children with fishsticks. However he did not actually believe that she was a prostitute until her pimp comes to pick her up.