This Looks like a Flatspin in Power Off Mode to me.
the Controls are a Mix between Pro Spin and Antispin.
The 52 will flatten out with Outspin Aileron immediatly. To perform the Ultimate Flatspin you would then add Power and go Stick fwd.
The Recovery from an Intenional Flatspin ( Power on - Outspin Aileron - Stick Forward - Rudder Inspin (( The Russians call it Superspin)) ) :
Power OFF
Rudder Opposite
Aileron Inspin
Stick full back (Otherwise Airflow over the Rudder is Blocked in a Flatspin)
After 2-3 Revolutions without reaction the Aircraft will bank in the Spin and enter a Normal Spin/Skidding Spiral Dive ( You can hear the Airflow reattach and the ASI will Speed up like crazy)
Then, Aileron Neutral - Stick Forward - Rudder Neutral when Rotation Stops and Recover.
So, everybody seeing Flatspin-Spin-Spiraldive is quite correct, but the Recovery Procedure hasnt been followed in this case. It Looks like the Attempts from Untrained (On YK52) Pilots.
The Pilot was a PPL that owned this AC for over 10yrs.