In general my experience has been that NVDA works well with MNathML and braille. However, in the case where there is an embedded table, NVDA doesn’t seem to show the content in braille, either when the table first gets focus in browse mode, or when you start interacting with the content.
I have several examples of this but they are behind a system requiring a username and password. There is one example I’ve found I can reference here at:
NVDA requires that you have the Math Player installed.
Are others able to reproduce this and before I file an issue to NVDA, does anyone know if this is already known?