Complex sentence: However, nobody of Headmeters knew who "I" or "I2" are, there is no information about the two in the memory bank of Fraud's computer, and "Headmeters I" is a missing number.
Split into simpler sentences: However, nobody of Headmeters knew who are "I" and "I2". And there is no information about the two persons also in the memory bank of Fraud's computer, and "Headmeters I" is a missing number.