Just tried calling SPG about this... twice.
First call: the agent was adamant that Al Maha is still part of the SPG program, SPG is alive and well and its Ts&Cs still apply.
He insisted that it's still 66k per night even though the app and website say otherwise, as it's an all suite hotel.
Second call: agent immediately confirmed that the cost has gone down. She cancelled my old reservation and rebooked at the lower rate in less than a minute. Refunded points are already in my account.