Thanks everyone for your input.
I initially was looking at the stopover policy wiki (new account so can't link the post) when typing up the OP, hence the discussion around the wet lease.
VI. Different scenarios for STPC
•QR is operating an immediate connection with seats available in the desired cabin, but the passenger has booked a connection with transit time of 8-24 hours. STPC is not permitted either complimentary or against a fee.
•QR is operating an immediate connection but no seats are available in the desired cabin. If the passenger has booked a ticket on the next available connection with a transit of between 8-24 hours, STPC against payment is permitted.
•QR is not operating an immediate connection; all the connections have a transit time of between 8-24 hours. Passenger may choose any connection and receive STPC free of charge. There are reports that this may no longer be correct.
I thought that I would qualify under point 1 but it seems I may have misunderstood that a codeshare also qualifies as an immediate connection. Curious why I am eligible for paid transit accommodation but not complimentary.
In any case, the Al Safwa lounge might not be a terrible place to pass the time especially if I can snag one of the rest facilities.