That was my understanding, too, Ana, but a) people in general (notably journalists) seem to know very little about this Foreign Office committee; they seem to have been surprised to find it even exists, let alone know anything about its procedures.
b) We don't know if the Queen actually had signed off this invite or whether T May knew it was 'in committee' and just pre-empted their decision and the Queen's approval. (I wonder what the atmosphere maight be like at the Queen & the PM's next weekly meeting...)
the Queen is in a difficult position because if it was done without her approval she can't publicly say anything.