Statement-I: True
Needamangalam Meenakshi Sundaram Pillai was indeed a renowned Mridangam vidwan.
He was a legendary teacher and performer who trained several important percussionists.
Statement-II: False
Palghat Mani Iyer was a legendary Mridangam maestro, not a Ghatam player.
He revolutionized mridangam playing in the 20th century and is considered one of the greatest percussionists in Carnatic history.
Hence, only Statement-I is correct.