Following a user's calendar migration, a series of recurring meetings were not migrated and NME. Verbose logs do not show any problem with reading the meeting.
No item is created in the target PST or Exchange Mailbox.
The source mail database in the Notes 8.5.2 client the entries appeared in a Grey Colour and were using the "Notice" form in Notes. The actual meeting had not been accepted.
1- Accept the meeting; the Notes document will be saved with the "Appointment" form and NME could read
2- Migrate the meeting.