Statement-I: True
Needamangalam Meenakshi Sundaram Pillai was a distinguished Mridangam vidwan.
He was a celebrated teacher and artist who mentored numerous significant percussionists.
Statement-II: False
Palghat Mani Iyer was a celebrated Mridangam maestro, not a Ghatam player.
He transformed mridangam performance in the 20th century and is regarded as one of the preeminent percussionists in Carnatic music history.
Therefore, Statement-I alone is accurate.