I thought this a very adroit offering that I much enjoyed.
Finding the confirmation may have been superfluous to completing the grid (but how could one be sure of that until one had the confirmation?), but was necessary to appreciating fully the art that went into the construction. It does seem unsatisfactory when an entry can be sent in without the (partial) solver having a full understanding of what was going on, but in this case it's difficult to see what else could be asked of the solver to establish that s/he had a complete understanding without that extra something seeming artificial and unconnected to the theme.
I enjoyed the cluing and the theme very much - thanks, Bufo.