It may sound silly but I too would go through all the hassle you have today to make sure I flew in F. It's not that I feel I can't travel in another class for this length of flight (I've flown that route 12x times in economy with no issue) but flying in Qantas F was a bucket list item for me and one of the most insane experiences of my life (even though many say it's comparable to business class). I will never be able to afford a business class flight with cash, let alone a first class flight with any carrier so flying this way is an experience by itself. (flew June 2022 and it was truly exceptional)

Glad it looks like you've got everything worked out. All in all, it seems like both airlines were helpful and even your worst case scenario wasn't bad.

Keep us updated on your flight and do be sure to post photos!