Fare claases on MH don't map to fare families that way they do for other airlines. Basically, O can be used for any of the families (eg. basic or flex).
IIRC it's the FL part in the fare basis that signifies Flex.
If 'O' is not in the table, it won't earn on QF.
You can basically calculate it as
Amount for Earn = Total Cost - GST - Amount Paid In Points
$75-$80 sounds about right, but earn would be more in line with the what Sudoer shows.
Worth noting the Stays Exceptions page has also been updated recently (and added a few hotels where you have to book three nights to get the StayPlus)
https://www.accorplus.com/au/stay-benefit-variations/
But it's not what the website says now. Perhaps they've changed it to reflect what actually happens
Either way, something has gone wrong with how they communicate or calculate rounding.
From what I have heard they got their SC calculations wrong (rounding down instead of 'to the nearest SC' (ie up) in some cases). The top-ups are to fix this,
My experience with other cards is that pending transactions can't be stopped by the bank. They either complete or not. I have twice (different banks) been told to wait until the pending transaction finalises before raising a dispute.