Estimate speed
Someone with more video analysis skills than me could provide a rough speed calculation based on the video using the aircraft lenght as scale reference? Surely it won’t be 100% accurate but I think that the Ground Speed reported from FR24 data is far from accurate and is not even close to the TAS experienced in the final moments. With 3000ft/min a 738 can barely keep 300knots indicated. With 30.000fpm there is no way the speed was lower than 600kts especially with so much potential energy from FL300.
edit: if no such speed was ever reached than a recovery attempt should be realistic, and if a recovery was even partially successful that means that the initial upset was probably not as catastrophic as someone might expect.