Complex sentence: The "Mufaddaliyat" on the other hand contains rather a random collection; apparently all that was remembered and perhaps some that was only produced in the 8th century and was not truly pre-Islamic.
Split into simpler sentences: The "Mufaddaliyat" on the other hand contains rather a random collection. Claims have been made, however, that some of what is regarded as pre-Islamic poetry is only produced in the 8th century and was not truly pre-Islamic.