I'll be in a better position to answer your questions in the second half of the year although I won't know specifically about FMI other than what I hear off the grape vine.
With regards to the Nay Pyi Taw and Yangon, according to the Myanmar AIP, there are no RNP approaches however they do have ILS.
Here's a link to the
Myanmar AIP with the approach plates and aerodrome data for
Nay Pyi Taw and
Yangon.
You would probably use
Mandalay as alternate as that's the only other airport in Myanmar that has an ILS.