Isn't this rather similar to a Lufthansa A321 incident that occurred Nov 5th 2014, near Bilbao, (Spain), where the aircraft experienced a rate of descent of 4,000 FPM before the pilots got the aircraft back under control?
Incident recorded here:
https://avherald.com/h?article=47d74074
And here:
https://aviation-safety.net/wikibase/wiki.php?id=171411